Your vet might carry it - mine did until they started carrying another brand. Call around to several vets, maybe one of them has it? It's not prescription you just have to get the regular strength not the double.
It's a powder in capsules about the size of a tylenol. You can feed them the pill or open the capsule and sprinkle the powder on their food.
I get it from Foster & Smith, but they don't say they ship to Canada. SmartPak doesn't either. I tried to find a website in Canada but it appears all of the Canadian "pharmacies" only ship to the US... what's up with that?
Maybe call some feed stores (Cosequin is used on horses, but obviously in a higher dose) and pet boutiques. Good luck!