Not sure why you would call them US teams. Perhaps Canadian teams in US based leagues and even then the NHL has offices in both countries. By the way, you missed two --- the Hamilton Tigers played in the NHL from 1920 to 1925 and the Toronto Huskies played one season in the NBA, 1946-7.
I think it's clear enough when I say "US Sports Teams in Canada" that I'm referring to teams in American sports leagues. Also, the Toronto Huskies played in the BAA (Basketball Association of America), which was a precursor to the NBA, so I decided not to count them. You're right about the Hamilton Tigers. I added them as an answer.
The Toronto St. Patricks/Arenas, Quebec Bulldogs were NHL teams, there are quite a few more who played against NHL teams for the Stanley Cup but I remember those two teams for sure belonged to the NHL. Not sure if the Quebec AC you mentioned and the Bulldogs are the same team or the Toronto FC and the St. Patricks/Arenas are the same team you mentioned either.
Bonus questions really get ya thinkin'! Fun stuff