I have been practicing zazen for a little while now. Because of there being no stores in my town, or more importantly because money is tight right now, I do not have the ability to get a zafu or bench (which I would actually prefer). In it's place I have been using a pillow, bent in half, but this is of course not the greatest support for my back. I know that I won't be a "proper" practitioner or not be able to zazen without one, but it helps in being comfortable when "just sitting".
My question is what could I use or do, in place of a zafu or bench until I can acquire one.