My best prices for supply and install have been from Eddie at EMS, Essential Motorcycle Service.
Last time I rode over there with my 1200 GS, I took the wheels off one at a time in the parking lot, let him carefully install the new tires. As is the case with a lot of suppliers, as long as you buy the tires off them, you can expect a free install/balance if you supply wheels off of the bike.
https://www.essentialmotorcycleservices.ca/ I do know the close 3 months a year during off season. Pretty sure they are open February 1st.