Bill,
There is only one answer and I see that Cabelas is carrying it now and that is Merino Wool. They don't have the brand I like but something similar. They have a couple different configurations in the catalog, the most recent is by Osterlund or something like that and is a 400 gram top and bottom long underwear. I usually wear Icebreaker brand and love it. Today out in the Marsh in the blowing snow I wore an Ice Breaker Merino zip top, a Filson Merino long sleeve top, a Filson Merino wool sweater and a Filson Merino Waterfowler sweater. A Drake 3 in 1 over it all.
I have searched far and wide for the ultimate under garments and Merino wool is the only stuff I will buy anymore. Try Merino wool and you will never go back to synthetics again.
Best,