Anyone know an online store that I can find Colt factory stainless 9mm & 10mm mags.

I don't know of one online.  There always seems to be a few of each at every gunshow though.  They cost an arm and a leg, but they are good mags.  I've settled on Metalform mags.  I use both 9mm and 10mm and they have worked 100% at about half the cost of factory.  I usually don't go with aftermarket mags, but they seem pretty well built and so far work fine.  

Ross

CDNN

Maybe you can find something you like here. I buy from them quite regularly.

Have been looking at the MetalForm too.  They are a government contractor.  Can buy 10 for $130 and they are supposed to be equal to Colt.  Just like the little pony on there.

Yeah, it's nice to have factory mags.  I only have one factory 9mm and one factory 10mm as I bought the guns used and that was it.  No boxes, no nothing, just guns.  If I could afford it, I'd buy factory mags as well, and may still get a couple if I find a good deal.  For range work, and general dropping on the ground, etc, the metalforms are a decent alternative.  They're pretty well made and have good springs in them.

Now I'm thinking about a 9x23 barrel for the 9 mil, but then I'd have to go buy yet more mags (38 Supers) for that.  I'm never done buying mags it seems!

Ross

I thought Numrich had them, but they're sold out now. Have you tried Colt? They also show up on Guunbroker at a fair price, about 30 each, but be careful you get the real deal. Metalform are Colt mags w/out the pony, and they also have welded on baseplates. Some people claim Wilson 45 mags work in the 10, some say they don't. I'm going to try tomorrow.

Edited:
I looked down the page, it's only the ones with bumper pads they're out of. $40-$55 depending on which ones you want.
www.e-gunparts.com/productschem.asp?chrMasterModel=0660zDELTA%20ELITE%20SERIES%2080