I would suggest purchasing his ticket online, and getting an e-ticket. I'm not sure exactly if they have etickets available for that location - but it would be your easiest route. That way he just needs to print it out and have his ID ready - no complicated issues with mail and all that.
Are you using Air Canada for the entire flight, or just while he is in Canada? becuase I would suggest using a different airline. Air Canada has recently changed thier baggage limit to 1 checked 23 kg item, an extra bag is $40, and more after that I think $150, and if any of his luggage is just the slightest overweight, they charge $100 per bag.
West jet on the other hand allows 2 pcs and only charges $40/overweight bag, and not to mention they are very friendly. I found Air Canada to be just grumpy overall.