I need some new pants for when the saint's go marching in.  I've got some Vertx pants I wear often and work fine but would like something like the Crye precision G3 pants  G3 or the UF pro pants (too many pockets)UF Pro
What other mfg's should I research that make a pant in Woodland M-81?

Platatac.

What's wrong with good ole surplus?

US made at least 2 types of woodland camo pants. Most common being BDU conventional pants of varying weight/composition of fabric.  Second being the M-65 "winter" pants having the capability of using button-in pants liners and GI suspenders (highly recommended-- suggest using pants with suspenders and relatively "open" waist to vent heat/moisture out of pants and into coat/jacket that is better able to disperse such heat/moisture)  These pants and liner usually worn over the regular pants, but can be worn alone.  Much heavier/stouter fabric than even the heaviest weight standard BDU pants.  Shop around for waist/leg sizes, and matching waist size liners.  GI suspenders still easy to find.  Not sure if this is what OP is looking for; just mentioning it as an alternative.

USGI Winter Pants  

Tru-Spec makes a 50/50 NYCO ripstop woodland pant based on the ACU pattern.

Beyond Clothing

Are there m81 crye pants? I know I've seen them in pictures before, but only have ever seen one sketchy link to get hands on them.

Before spending a $200+ on a pair of pants I would wonder how much you have spent on other stuff for "when the saints come marching in."

Do you have more ammo, food, batteries etc than you can carry?
Than your vehicle can carry?
What's your NOD setup like?
What are your COMs like?
Your body armor and other gear?
Spares for the friend who was out of town "when the drums begin to bang?"

If none of those things are 100% squared away I would suggest a pair of Wrangle cargo pants or died UCP until they are.

The most useful thing I can think of for most folks concerned about "when the stars fall from the sky" is a gym membership.  

I don't know you and I'm not trying to call you out, just wondering how you (or anyone) might be prioritizing.

Plus I have enjoyed the Saints reference.

No experience with them but beyond clothing makes a ripstop m81 pant

And their ordering/shipping process is flawless!

No one gives a shit but after 2+ decades I swore I'd never wear Woodland cammies again!

Suggest that Currahee's comments above are worth considering.

Woodland Camo is the new coolness, particularly in some locales.  Perhaps because it is generally useful, perhaps because it is still avaiable for cheap on surplus market, and available in multiple sizes and torso/leg lengths.  The "window" of surplus availability for all these sizes is drawing to a close. YMMV.

Suggest ordering pants at least one, maybe two sizes larger in waist to accomodate winter garments worn underneath pants, and using suspenders in lieu of waist belt, as explained above.

GI BDU trousers are always tight in the crotch, and often "blow-out" there.  Ordering GI/Milsurp trousers in larger-than-usual waist size in order to provide room in crotch area is a proven Good Idea.

I can say, from personal experience, that wearing a "size-up" from "normal" GI BDU pants, and also using decent suspenders instead of a belt, makes for a FAR better shooting experience on the typical shooting range, and I reckon a much better shooting experience on a "2-way" shooting range.

Your clothing should fit you, but NOT restrict your body movements in any way.  If your clothing restricts your body, or movements of your body, suggest different clothing.  Suggest buying clothing from a mfr/vendor with a decent return policy.

I have heard of some folks wiping-away any sort of water-proofing on GI Woodland garments with alcohol, and "sponge-daubing" parts of the black areas in such GI surplus clothing with terrain-suitable and non-IR-reflective paint.  Brilliant idea, IMHO.

How a particular clothing Mfr tailors their particular clothing makes all the difference.  A Mfr that tailors their clothing for a young, fit, 18-year old Soldier/Marine might not fit your different body.

Personally, I "could" afford multiple $1000 dollar combat clothing items.  I reckon that similar and multiple USGI items might be money better spent.  I don't think that buying expensive and high-end items is a wise way to spend my money.  There is a huge difference of opinion about this, and I respect differing opinions.

Just to say, I don't have Uncle Suger funding my initial purchase, nor providing/sustaining my future items.

"Choose Wisely".

Another Vote for USGI.. hard to beat and relatively cheap... I dumped all my MC stuff when big Army went to Scorpion/ OCP whatever they are calling it this year... Even had a custom set up made for my BALCS armor...  Here in ENC woodland is a good choice!!

Everyone has their personal choice, based to AO conditions/terrain and how garments fit their body.

I retain a lot of MC/OCP items since they are "generally" useful, but I have other clothing/items.

As always, YMMV.

Yeah, I've been on their notify list forever. I'm pretty sure there's no restock coming.

I would NOT recommend SEMAPO Gear (Korean knock offs).  Tried them and they just are not built for guys who aren't very small framed unless you like that skinny jean look.  

Used set of Cryes or Platatac.  Something constructed by a company with Western bodies in mind is what you want.

Yeah, see that's the problem from my point of view is that having to custom stuff is a PITA.  

By going with Multicam I can pick up now the surplus stuff coming to market now and presumably more of it in the next few years that is still "new" designs and not stuff designed in the 80's and 90's. Looks Gucci if you can M81 Woodland with modern carriers and so forth, but too expensive for me.  Like I have the full modern  PCU Levels 1 -7 (with the exception of Level 4) and I got them at an affordable cost in Multicam.

Typical (predictable) and seasonal vegitation in your AO will determine what camo patterns/colors are most useful.  If hunting game, your scent (and noise) will likely be FAR more revealing of your presence than your specific camo gear.

If you need button-in insulation within your pants, you are likely in a very cold climate, perhaps bordering on Arctic.  Huge difference between "Cold-Wet" climate, and "Cold-Dry" climates.

Old-style USGI-pattern camos might be "reasonably" close to what you need.  Most USGI clothing items are available in multiple girth/length sizes.  Sometimes for very cheap, if one shops around.  Strongly suggest that "used" GI items were laundered with wrong detergents, and so MUST be re-laundered and rinsed, many times, with correct non-IR reflective detergents.  No Expert, but there is some evidence that GI clothing that was laundered with "improper" detergents can have some of that IR-Brightening "washed-out" given enough washes/rinses, and proper washing chems.  Again, No Expert.

Your specific game animal just might be able to "see" your garments that were inproperly laundered.  Some Humans might be able to "see" your improperly laundered garments.  Suggest assuming ALL surplus GI garments were improperly laundered, and take appropriate re-laundering measures.

Suggest, If going with USGI surplus clothing, that M-85 camo pattern being most useful in forested, shaded terrrain.  USGI "Desert Camo" being most useful in very brown terrain.  The USGI  Desert Camo (Two types--Six color and Three-color)) was limited in production, and some items are becoming "Collector's" items, with prices to suit. "Desert" camo can easily be dyed to a slightly more brown color, but caution is suggested.

Perhaps not a bad idea to position slightly different, but differently terrain-appropriate, pouches on your PC/Chest Rig.  Make up your own "disruptive" camo scheme with your terrain-appropriate gear.

In winter, with snow being on the ground, it seems reasonable to have white pants, and upper clothing to suit trees/vegitation in your AO.

I'm no Expert, just trying to offer common-sense advice.  I'm sure others will differ.

I'm probably not going to buy a very expensive pair of excellent aftermarket pants when I can buy ten "decent" surplus GI items for same price.

At this point in my life, I could afford to do so.  Being both thrifty, and more than a little skeptical about "some" high-end items, I'll refrain from the "High-end" clothing items that Uncle Sugar seems to pay for.  YMMV.