On the area of roll cages, first of all, I have to ask, why?
Not that I'm against them; I have a full roll cage in my car. Then again, I race with it, and run multiple driving schools with it, so it's pretty much a given.
In order to get the proper cage for what you want to do with the car, I need to know a little about what your plans are for the car.
Will it be a track car, drag car, street car etc? Or all three? Is cost a factor, do you need access to the back seat etc, etc.
A couple of other places that do roll cages as well include Mantis Racing in Oakville, and CSC Racing up in Newmarket.
Raven / Bavarian did excellent work on mine, but I've heard excellent comments about Ronny at O'Brien Motorsports as well. I'd highly recommend either one of those to start.
I'm not really an asshole, I just play one on the Internet