I noticed Costco now has poly/merino wool underwear for about $18 each. Should work good.

I usually wear poly underwear, blue jeans and have rain gear with me. I make it a point though to stay dry. I don't hunt in the rain and hole up if it is snowing. I found out a long time ago, elk hole up in a snow storm but you had best be out there right away after it stops snowing.

If God wanted you to walk and carry things on your back, He would not have invented stirrups and pack saddles