Any cloth can be used for bow backing. IMO, the thinner the better because the more glue you use the heavier the backing will be. That is why linen and silk are so good. They are both thin but strong. Silk is very stretchy and linen hardly stretches so I don't think stretch matters that much. Once glue is added the backing becomes more rigid anyway.
Thin cotton cloth should be OK. Cotton is more absorbant so it will soak up more glue so use a thinner cloth. Also, you want the glue to completely saturate the cloth for best results, making it a matrix of the glue/cloth similar to fiber glass cloth and resin.