I need scrap canvas

[guldan]

I'm contemplating an art project and am hoping to scrounge a few supplies for the experimentation phase. I am in need of painters canvas. I'll likely be cutting down to strips of 4"x10" (or there about) so scraps are great. Unfortunately, it does need to be reasonably clean (no paint already or things that will irritate skin too much).

If anyone has some that they are willing to toss my way, please let me know!