Our Daughter was born in Doha in January so we recently had to apply for a citizenship card and passport for her. Most photography shops in Doha have the specs for Canadian passports (if not they are on the application forms you download off the net). As for Courrier, it may not be the only one, but we used Fed Ex. It may be a little more expensive, but since we had to include original documents, we went with a name we knew and trusted (and could track our shipments progress online).
Hope that helps, good luck to you.

Stay safe.

Perfection does not exist. The question therefore, is: what level of imperfection are we willing to settle for?