I booked with the Door Company. They haven't done the installation yet (they are coming in 2 weeks), but they had good feedback on another forum. The person who answered the phone seemed knowledgeable.
http://www.buildinghomes.ca/community/f ... ion&page=2
Their number is 613-821-2130. Cost is $155 + GST and includes reinforcing strut. There were cheaper places, but their BBB ratings were brutal and I didn't get the best vibe over the phone, either.