Well... I`m going to respectfully disagree with you. If there is something made by AI that you want to buy, and you are in Canada, I would suggest contacting Rob at Wolverine and letting him know what you want and he will order it for you. Wolverine is the exclusive Canadian distributor for AI products. You are correct that there are multiple distributors in the U.S. (Euro Optics Ltd, Mile High Shooting Accessories, SRT Supply Inc, and Tac Pro Shooting Center) but that doesn`t do a whole lot for buyers in Canada unless you are going to do the paperwork yourself to import firearms and parts into Canada, or work with a third party importer.
In my experience working with Wolverine, they can get anything AI makes no problem. All the models and calibres you have listed should be no problem at all. Some of the calibres you mention are not stock AI calibres, but I believe what they do is get Border Barrels to make up those barrels and they will ship them out with AI roll marks on them. Some of the barrels people use with AI actions in the U.S. and elsewhere are also, of course, aftermarket. Wolverine doesn`t stock everything, nor do they list everything on their website, but just let them know what you are after and I would be really, really surprised if there is something that comes out of the AI factory in Portsmouth that they can`t get. Certainly any AE, AW, or AX is not going to be a problem from what I have seen. Whenever I ask them about something AI they always give me a big long list of options I can order, barrels, accessories, parts, etc. I just can`t see where the problem would be.
Unlike most other manufacturers I can`t see how anything made by AI would have much in the way of legal restrictions on importation. They are all non-restricted bolt action rifles. Maybe one of the Wolverine guys can chime in on this but, if you want an AE in .243WIN, or whatever, I can`t see who else you are going to work with to obtain that product unless you are going to put in the leg work to import it yourself from the U.S. or England. I would suspect that all four U.S. distributors and England are all going to tell you to call Wolverine anyway.