You can get DHC6 put on your Canadian license if you have a PCC/PPC or FlightSafety course certificate by applying to TC. Many foreign countries require your license to actually show the rating even though it is not required in Canada.
As for the original posters question. If you think your chances of getting a job flying a Twin Otter as a 200 hours wannabe is enhanced by you going out and dropping 13 K dollars at Flight Safety then you truly don't have any idea how aviation works.......