Just try getting white or yellow cedar in Manitoba. The store I enquired at says it is only available from the east coast, but apparently yellow is available west as well according to you fine folk. So, if I were to orded this fine eastern white cedar it would be 3-4 week wait and $10 a board foot. The nice fellow suggested I just use red since it is a superior wood anyway.
With all due respect to the nice fellow at the lumber store, there is no such thing as "superior" when it comes to wood. Rather, there is "best suited to task." There is a reason that most of the east coast canoe factories reserved their stocks of white cedar for ribs (because it bends much better), and imported western red cedar from the west coast (because it was available in long lengths, clear and vertical grain, which is better for planking).
Your (roommate's) Chestnut will have white cedar ribs and planking. If you want to restore with like material, I bet there are a number of builders in Ontario, Quebec, or New Brunswick who could ship you what you need in the way of rough or finished rib and planking stock. Heck, Andre is in the midst of moving - he should send you some of his just so he doesn't have to move it!
If matching doesn't matter, by all means use red cedar for the planking, but follow the lead of our left-coast experts who have used yellow cedar and are experienced in its bending qualities - I've not yet had the opportunity to use it.
Anecdotally, some years ago I sold a 15' Chestnut to one of our upper midwest members, who repaired it without too much regard for matching wood. The canoe was nicknamed "Patches." While he enjoyed it for several years, he was never really happy with how it looked, and was relieved when he sold it after obtaining a better 15'er...