Some have the "X" stamp, some do not. Some have the plum colour added to a number of the parts, some do not. I have examples of both and boy do they shoot damn well!
I haven't seen very many Canadian vet bring backs. I only know of one all matching bring back but it is with a friend who will never sell it as it was brought back by his grandfather (believe me, I've tried!)
The one or two others I saw I think had mis-matched bolts to the rifles but that appears to be common with them, even on U.S. vet bring backs.
Be prepared to wait for quite a while as all matching, not post war dinked around with, Kar98ks are a special rarity in themselves in Canada.
You may consider dipping down into the U.S. for one but having to deal with an importer and related costs they charge are a real deterrent to this option for most.
RCs, for instance, usually go between $400 and $500 depending on condition, year made and maker stamp, and parts on the rifle. You can sometimes luck out and get uncommon codes or years this way for cheap. A well priced RC is sold on the EE probably within 30 minutes of the ad being posted.
Best of luck with your hunt.