Wally-World Wenzel aluminized 1/2 in. pad
I've never seen this in their stores and stumbled over it online. 71 x 24 x .50 are the specs. The are suggesting that the aluminized surface will reflect your body heat and keep you warmer. Makes sense to me! It gets good ratings from tenters and cot users.
At $9.97 and free ship to store it may be worth a try. You could cut off about 30" and tape it back together across the remaining piece for a 64" length pad? These might be good for my sled dogs when we go winter camping in the BWCAW. I currently put a cut down yoga pad in a burlap sack with some straw. That way I don't loose the straw over time and it keeps the dogs drier lying on the ice on a closed cell pad in the sack.