I'm not in canada, but I'm sure its like here in the states with the older type bills. If someone brings them to the bank and the tellers don't snap them up, you may have a chance at finding them. I'm not sure if they are still legal tender or not though. I"m sure someone from the Great White north will step in and answer this.. I"m quite curious about it too.
don't think so because they are turning them in as they get presented to the tellers.That is my take.