Move to the states.
Yes, there are convoluted ways around this; there are good threads about that here.
I am finding kobobooks has a good selection of titles. Have you checked Sony's site as an alternative?
Generally, if an ebook does not have Canadian rights, no one will have it. If you find Amazon sells a Kindle version of the title in question, fire off a note with the specifics to Kobo and they may be able to "turn it on" in Canada. I've had that experience already.