I've been looking for the USMC Snow MARPAT oversuits for ages... Well I've found this:
http://www.techmarkentinc.com/page656.html
Dunno if the website is legit tho...
And a bit expensive for snow oversuits that I'll use what, 2 times a year? But it's the first time I've seen them available for sale like this... I want them. I fucking want them. But considering I saw some of them go for 150$ a piece on eBay... it's not that bad either.