Cost of Canoes?
I hate to undercut the many craftsmen out there, but here in Philadelphia there is a guy who builds very high quality 15' and 18' wooden canoes, which he sells almost exclusively to a camp up in Maine. His 18' boats go for around $1500 depending on specifics. I've paddled his canoes and they are joy, not to mention they will take a SERIOUS pounding by little kids and keep on going.
Another possibilty -- I STRONGLY support Dan's suggestion of having your campers be a part of building or restoring the canoes. I was a camper at the camp in Maine that I spoke of and we built canoes there every summer. I then went back and worked there as the resident builder. Being able to take part in building the canoes is not only tons of fun for the campers, but it makes a HUGE difference in how they take care of the wooden canoes. Good luck!