I live near Buffalo, so you know how COLD I get! I have found a tube sock filled with feed corn heated in the microwave is the best for my feet, and I have a lg. buckwheat filled pad that I heat for my neck and shoulders. I have found if I go to bed not so bone chilled, I don't seem to get so cold in the night. Have you tried thermals from a sporting good store? The kind they make for winter camping, or hunting, that are light weight and wick moisture.
Hugs, and hot tea with lemon,