I'm going to get flamed for this (seems anytime I say anything about anyone or anything French, I get piled on, but here goes), but in my experience (and I've been to France and Montreal both numerous times, so that makes me an expert without equal), Montreal's gastronomic tradition is unique in that cassoulet does not seem to really have much of a place. Cassoulet is considered Southern French, and while I don't know the geographical origins of the French who populated Quebec, I don't think they were of the South, because cassoulet is only on menus in expensive restaurants, and the little people's places serve things like crepes and smoked meat, which is Northern. You can't even buy canned cassoulet in the supermarket!
Frankly, one of the things I love best about visiting Paris is buying cans of cassoulet at the markets like Le Bon Marche - they are so good! As it is even at the corner Bistro down the street...
There's a restaurant in New York here, Au Gascogne (IIRC), on 8th Avenue - I took an old girlfriend a couple years ago and ordered the cassoulet - I remember it was very expensive and very good - JUST very good, not excellent - it was not very creamy, as cassoulet should be, and seeming undercooked. I enjoyed it, but I took from that experience that paying a fortune (something like $25.95) for a dish of French-style beans and sausage anywhere outside France is a bad idea.
Can't tell you about the Choucroute in Montreal.