The Target by us has a $1 bin and just got in a bunch of cheap-o camping accessories. Among these is a "waterproof match" set, with 100 matches and a plastic "waterproof" cylinder to store them in. I don't know how waterproof this really is, but for a buck, it's worth looking into. The tube is about 3 inches High and 1 inch wide, plenty big to get a list or even mini swag into. It has a screw on cap with a rubber ring to seal it. The other $1 stuff they have might make good caching gifts as well (cheap pocket knife, first aid kits, emregency blankets, etc).