Not sure if you meant this for me or the OP but I will try to answer.
If you are not a permanent resident of Canada you have to pay for healthcare here too. Unless you are visiting and have health insurance, but surgery sounds like it should be scheduled and they may deny that being covered by traveller's insurance.
Good point though - the surgery may be less expensive here in Canada than in the US however, and the dog could travel here with just a valid Rabies certificate from the US and no fuss!