Denim or Canvas (Dublin and Union)

I am in need of a large amount of denim, canvas, or similar textiles for an "upcycled" shelter project I am working on. If you have old jeans or corduroy trousers that you are going to throw out, or used canvas tarps or drop cloths, or anything else made of these materials, I would very much like to keep them out of landfills and use them in a way they will continue to be useful for years to come!