I have put hardwood (oak, maple) gunwales on some canoes I intended to keep. They look good but add considerable weight to the canoe. If your goal is to do a restoration, then sell, you will most likely not recoup your costs.
Many canoes built before 1920 were built 'closed gunwale', meaning the rib tips were shaved thin, tacked to the inwale, and outwale tacked to the outside of the hull and a cap tacked over top the both of them, thus hiding the rib tips. Looks fine, but water evaporates more slowly from the enclosed space, so more rot prone. The transition to the open gunwale style of build where you easily see the rib tips sandwiched between inwale & outwale, occurred over years in the teens and 20's.
HW has been debated often. Doubtful it can be confirmed. Tom McCloud