I dislike Rush so I wouldn't call them a must see. I'm not into their sound.
As far as super popular Canadian bands go I'd rather see The Tragically Hip, love, love, love them. They just played Massey Hall with tickets $90 a pop though so I'd guess their fee is quite hefty.
I'd love to see this guy at Mac, Joshua Bartholomew. He's an independent Canadian artist, based in Toronto.
http://www.joshuabartholomew .com/
I've purchased both of his albums and both are amazing. He's such an amazingly talented young man.