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I did some research on that area a year or two back when I first heard about Horseshoe Bend, although I haven't managed to make it there yet!
The only airport that is remotely close is in Page, AZ. Great Lakes Aviation has a number of flights there, both under their own name as well as under United codeshares. Frontier also have a small number of flights from Denver. Prices vary significantly, but if you book a bit in advance it looks like sub-C$300 is possible from YVR which is a pretty good price!
Other options would include flying into Las Vegas (often good prices, and cheap car rental!), Flagstaff or even Phoenix and driving, although it's not a short drive!
If you've got some time to spare, I'd suggest flying into Las Vegas and driving north to the Zion National Park area, such as somewhere like Hurricane. You can then spend time in both the Page area, as well as Zion which is an amazing place!