You simply have to follow a bunch of rules and red-tape and that stuff is doable. Suggest you contact Denise Tiffany at Leroy's Big Valley Gun Works in Glasgow, MT and she will explain how you can order and obtain that stuff. She is an importer/exporter that really does a fine job for a lot of folks in western Canada.
There are others who can do this also, you have to be patient and go through the hoops. I did an article a while back on this, easier for stuff to go to the US than it is to come back this way for sure. There are also Canadian suppliers who get lots of good stuff up here, you just have to find them. Friend of mine just got a special stock ordered up through Bashaw Sports in Alberta, they got what he needed and he's shooting it now. Might talk to a fellow named Pud at that shop, he helped my shooting partner recently.
Same goes for taking rifles across the border for hunting or matches - you have to have the papers in place and it is no sweat. Takes time and a bit of effort to get the papers but no choice.