Couple things I've noticed with CP (thats canada post, not child p*rn for the RCMP/CSIS guys reading this) is that the prices to ship are much lower if you register as a small business online(its free and you don't need to actually have a business) and do the paperwork (address, size, weight,print out the shipping label) through the inline portal. Was about 35% lower than just going to CP and typing the dimensions in on their open website.
Second, Canada post doesn't know its a firearm, doesn't want to know its a firearm and shouldn't know its a firearm. The instructions are quite clear, DO NOT LABEL IT AS A FIREARM! The last thing they want is their people (in house staff and contractors) knowing what is in the package, esp pew pews. Doesn't take much for a rogue delivery person to text a friend and say 'i just dropped a package with a oew in it on this doorstep' (although shipping a gun should always require signature and age verification, to cover your ass in making sure it gets to the right oerson).
Yeah, its expensive. A government run corporation, what else would you expect?