I would not sweat it as far as Canadian sources goes.
You can order the stuff, pay shipping, GST/HST, and any other fees, or you can buy the stuff from a Canadian guy that bought it from the US, paid shipping, GST/HST, and any other fees, then marked it up enough to be profitable before he sells it to you so you can pay shipping and GST/HST on an all new higher price.
If there are Canadian makers of these parts, I'd love to hear. Other than a couple custom makers, using imported parts, and one outfit that seems to mainly sell India made replicas, the pickings are pretty slim.
Get a Track of the Wolf print catalog. Good, life size clear photos of most of the action and lock parts. Pretty much the same hardware as everyone else has available, in a broad range of qualities, from pretty cheap, to really nice.
Once you home in on a style or name, you can then search for alternate sources and seek out better prices if you can find them.
Cheers
Trev