I suppose it varies, but the Canadian medical costs about $100 where I've gone (in YYC), BUT, if you go to the right examiner you can get a CDN and FAA done at the same time, my AME charges $150 for that...
I'm sure that the Aero course is a decent course, but I'm not sure that you need it to do the exam... it's 25 questions... mostly regarding the differences in Air Law. So if you look up the regs, read through them... there you go.
At the exam though, it is 4 question multiple choice... two of the answers are usually very close to each other. It would probably be worthwhile doing some of their practice exams to understand how similar the answers can be...