Sorry didn't get back sooner completely forgot about this thread.
I live just outside of Montreal and I never camp nearby, that said there is one CG highly recommended and all within 30mins of Montreal outside of rush hour. It's on the south side of the island which is easy to get to from the USA without going through Montreal with TT. The CG has all the amenities including heated pool, golf etc. It's called
Camping Alouette book soon as it fills up quickly also try to get a site further back.
Happy camping and welcome to Montreal.