iPad Verizon iPad 3 in Canada

I am taking a trip to Canada later this summer. I currently have a Verizon iPad 3 (from spring 2012). I believe this iPad, despite being on Verizon, does have a GSM radio that should work on Canadian carriers. (in addition to its CDMA radio for Verizon).

I am trying to figure out the best method to get service in Canada. How do I go about doing this? Ideally, I'd just like to either go into an Apple store or carrier store in Canada, buy a SIM card, put it in the iPad, select a plan, and be off. But from reading on the Apple support forums, it seems like I maybe need a Canadian credit card number to pull this off (I live in the US). If they let me buy a SIM, will it just work in the iPad or will I have to fiddle with the network settings to make it work?

Also, if any Canadian Apple fans know, which Canadian carrier has the best coverage in the Alaska Highway area? I know it's basically the middle of nowhere and a dead zone, but I wasn't sure if anyone had some kind of coverage there!

Thanks!