Bob Pr. said:A best source of info is someone in Canada.
You might contact these sources which I've been pleased with, both in service and prices; they can tell you if they do and what the prices in $$Can. currently are:
For meds I usually use Pet Shed because they've consistently been cheapest. Drs. Foster & Smith are usually much higher. But Pet Shed doesn't carry some things (like "Musher's Secret") and KV offers it at a great price.
For some meds (heartworm, e.g.) you'll need a prescription from a vet before they'll sell and ship. I don't know what the regulations are in your province. In the USA, in some states, vets can legally refuse to give a prescription, in some other states they must give one if requested (providing they prescribed that med for your pet).
Frontline doesn't require a prescription so that can be ordered w/o hassle.