[Amber H.]

M.-
Call Rose City Textiles in Portland Oregon (They should have a white page listing) and see if they still carry a heavy duty rip-stop nylon shell fabric often used in tents and parkas. They are an overstock type firm that specializes in outdoor and sports fabrics. I used the as a resource for tent making some years ago.
P.M. Me if you need some solid instructions on how to give extra strength when attatching loops or grommetts

Dont bother with canvas or denim. Go straight for the rip-stop. It is designed to resist the punctures and tears you are talking about. trust me on this. I have designed children's clothing and outdoor equipment for many years.