You do not have enough hours to write the ATPL exams so I believe you would have to do the CPL exam instead and then do the ATPL exams later. There isn't a frozen ATPL system as such, although you do get 2 years once you have written the exams to do the other ATPL requirements, but you need the hours. I think it may be 1500 but someone may correct me on this. Do not worry, they are cheap (ie around $100 each), unlike the JAA ones. If you want to fly 2 crew aircraft you write the IATRA exams which are similar.
You will need to do a flight test which, again since your hours are low I believe will involve an instrument rating flight test and possibly the elements associated with a multi-engine flight test as well.
And you will need a Cat 1 medical (done by a Canadian AME, this can be done in Europe there are a few around but its cheaper to do it in Canada).
I think that's about it. The full detail is all available on transport canada's website
www.tc.gc.ca.
Hope this helps.