I have hit 94km/h on a hill we call "Big Black" up near collingwood, but like Charlie said there are plenty of 100km/h + hills all around southern ontario, but only if you have the balls to hit them, and by that I mean ripping through 4way stop lights at the bottom of the hills.
Depending on where you are located, Grimbsy is full of 80km/h and higher hills as well as Hamilton has many more to offer.
Seems like you are a pretty serious rider, you should try and hook up with one of our sessions we have planned out on Ontario Longboarding Forum always looking for more riders to rip with and learn from.