If you're in the TC's - I'd suggest you go over to Northwest Canoe and discuss with them. They sell cedar-strip building supplies and epoxy - and they do boat repair.  They'll point you in the right direction.

For West System - 105 is the resin , the 2.. is the hardner that turns the stuff into glue/solid.  There are different hardners for diff needs.

Recoating the bottom of a canoe isn't rocket science - but a really-quick curing epoxy might be hard to work with.