I have a "Swiss Gear" Cot, It folds into fourths and the material is canvas. This is the most comfortable thing I have slept on. It is firm but not Ground hard. It is approx 7' long (I'm 6'2") and about 24" wide. I take it everytime. I cannot sleep on the matresses they kill my back and cannot do anything the next day the ground would keep me awake.
So here is the link to one just like mine. I got mine from the auction in brand new condition for about $15
Wenger Swiss Gear Comfort Cot | Overstock.com
Good luck