I need 2 bunk bed mattresses for my hunting lease camper so nothing expensive. Size is 31 �� x 75 ��. I�ve checked Ebay, Amazon, and several local camper / RV dealers and am striking out except for the high dollar ones. I�ve looked into high density foam but haven�t located the right size. I found some 5� locally that is 24� x 96� that can be cut and run across the bed but wondering how that would work out with the seams. It may be okay once I put a cover around it. Anybody know of a good place to look and what other alternatives have you used for bedding as opposed to a mattress?