Ok first off, guys are dumb. I'm not trying to be mean but they really don't have the same attention to detail as we do and its true, in the end they don't really care. Example, my fiance doesn't think spending money on invites is worth it and wants to send out email invites!
Ok but enough about me, I think the best thing for you to do is wait til you hear from your supplier about shipping to Canada. Tell your FI that you're looking into all options right now and want to base your decision on what is most economical but still getting what you'd prefer. While its a big help that your MIL is willing to plan and help out, ultimately the decisions are yours to make.