Thanks for the help and advice everyone.
Just as a bit of follow up:
In the end, I had a good friend from Ohio offer to order the parts for me. He ordered them to his address, and then will ship them my way once they arrive to him. I couldn't use my Canadian paypal on the site to send to an American address, so he just used his and I paypal'd him back right after. I saved about $200-250 Canadian at the moment, so even when I go to pay for the shipping from Ohio to Manitoba, I should come out ahead quite nicely.
I believe what made the biggest difference in my order was a set of stern lolipop side rails. if I didn't want those, I believe the shipping and duty to Canada was a fair bit better. Not sure if due to their dimensions, or what was the issue. But in the end I got the rails, along with 124 other parts haha.