I would recommend before wading in to the expensive hobby of militaria collecting that you obtain one or two reference books, that should be useful in answering some of your questions.http://www.servicepub.com would be a good first place to start as a fine publisher of books related to Canadian Army uniforms. My own book "Dressed to Kill" covers some of the topics you touch on, including the use of trades badges during the Second World War, etc.
Dan has covered brigade markings and the use of the French Grey stripe by the CAOF - these markings are illustrated on the website to which this forum is attached, also. (Look under ORGANIZATION and INSIGNIA for some examples).
The headdress you are referencing is the Field Service Cap, sometimes called a 'wedge cap' by collectors.
There is a listing of other reference books on the website as well in the RESEARCHERS & COLLECTORS section.
Note in particular the review of Skill at Arms - A History of Canadian Army Trades, including their Badges, and Parachute Wings which discusses trades badges in great detail.