I am looking for a good LBE duty style holster, however, I am not a fan of the new serpa style slick open top kydex holsters.  I would like something with a flap to protect from elements like the old bianchi M-12.  The holster is for a Sig P320, and the gun will not fit in a traditional M-12, so I am looking for close alternatives with closure flap.  

Again, this is for an LBE so it has to be able to fit on a USGI pistol belt.

Thanks!

Kramer lists the P320 for their field holster. I don't know about LBE attachment, but you could contact them. Also, the Bianchi UM84 should fit a P320. It fits every other full sized pistol and it' LBE compatible.

M12 with drop thigh rig

I bought this^^^
It is awesome.
It has the plastic part around the trigger guard like the UM92 version

The UM84 and other M12 style holsters will not fit the P320.  The P320's frame is too wide with the modular trigger group feature.  Believe me, I have M12's, I've tried.

I'm not new to hand-guns, but I am new to Kydex holsters, but not in a good way. I recently bought my first Kydex holster for one of my Glock 19s, and it fit the holster good and snug, not too tight or too loose. But after inserting the pistol in and out of the holster just a few times, it scratched the he** out of the finish on the left front of the slide. I guess a sharp burr or something inside the holster snagged on the finish on the slide. Thing is, I did a lot of research on which holster causes less finish wear, Kydex or leather, and I guess I made the wrong decision based on what I read, or got a bad holster right off the bat. 

A lot of people say that is normal; well, yea, maybe after hundreds of times holstering the pistol in and out of the holster, and not just a dozen times. 

I don't blame you for wanting an old-school leather holster. That will likely be my next holster, although I've ordered some thin suede leather sheets to line the inside of Kydex holster, although the damage is done. (I don't like for something to get the best of me:-)

Here is a thread I posted about it on the Glock forum... My first Kydex holster experience (not a good one) 

I actually don't want leather as that doesn't stand up to the elements, I'd like nylon like the M12 or some synthetic tough material like that.

I think I'd start with a surplus M12.  They are cheaper.  The Bianchi's differ from the M12 in having a longer "plastic" insert  to shield/support the trigger guard area.  It's riveted in similarly to the M12 and also at the corners of the plastic frame for the holster body (holds the flap and belt clamp).  It seems like you might be able to drill out the single M12 rivet and insert a thicker spacer.  You might also need to cut the threads down the edge of the holster and maybe add a longer spacer.  An upholstery or shoe repair shop could probably resew if needed or maybe some sort of glue/expoxy or fiberglass.

Although I'd expect properly treated leather could stand up to the elements, it did for centuries.  But that's dealing with a custom holster maker and might be a bit pricey.

Fuck I'm old. I was there when that was the hotness that replaced the WW2 style leather one.