Pre-1898 guns can legally be shipped across borders without an importer/exporter according to US law. I am not sure of the specifics for Canada but you still need to clear Customs on both sides and that at times requires a Customs agent which adds a fair bit of cost. You might try contacting these fine fellows and see what they would charge to clear the border, they have been very cost effective for my to use bringing guns out of Canada:

https://www.borderview.com/

http://www.bertramandco.com/
Booking African hunts, firearms import services

Here for the meltdowns