If it were up to me I would just take an AF Nikon and a 50mm and lots of film. Always worked really well for me. Winter is good for snowy mountains and the light is easy to work with because the sun rises late and sets early so you wont have to get up early or stay up late. Even during the day the sun will never be high so the light is mostly good, provided it is not overcast, in which case it will be flat and you may need to do lots of N+ development. Flat light is good too. Bring a lens shade and some filters and get a few pairs of woolen Norsewear gloves and a beanie. Dont forget spare batteries as they could be hard to find outside of big towns and the cold is hard on them. CR123 easy, CR4 hard and expensive.

Hope you freeze your nuts off. Bloody Okker.