CPL is VERY easy- its a 20 question test on Canadian air law, and you must have a valid Canadian medical (many AMEs near bordering states can issue Canadian medicals as well).
The CFI bit is a bit more complicated, I believe you still have to go through their instructor process, though some credit may be given for being a CFI under the FAA.
On a side note, what I find most interesting, is that you actually do not need any instructor ratings in Canada to give Multi Engine instruction- only a CPL and 500 hours of flight time.