MountainMan49, I would try a Pacific Outdoors Equipment pad. The one I'm currently using is the Elite, which at 15oz has core insulation only and probably only good to freezing. There is a warmer pad, the Peak Oyl Elite, which is apparantly really good when cold. I found one on Backcountry:http://www.backcountrygear.com/pacific-outdoor-equipment-peak-oyl-elite.html
I'd highly recommend these pads and the price is right! If you enter the BackcountryGear site via the connection off this site to the right, you'll make everyone happy!