If you are going to be on the Canadian side anyway I would suggest a campground on the Canadian side as thats also where there is more to see and do.
For campground recommendations:
Niagara Falls: KOA Lundys Lane has always served us and our friends well
Ottawa : Recreationland Campground
Montreal: Depends on where you want to be:; West: in Hudson Quebec: Camping Daoust
South: KOA Montreal South
East: Camping Alouette Saint Mathiew dr Beloeil
Quebec City KOA Quebec City.... Much nicer than camping Transit which is close