You said a "few months" when you posted this back in Nov, so hopefully you are still checking.
I don't know about taking critters through Canada. You are going to have to search around for that info. Try contacting an official customs or fish and game site.
As far as Alaska goes, only venomous herps are illegal, unless they are illegal at the fed level. Luckily, most stores don't seem to sell green igs, but if you can get one, they are 100% legal. When you think about it, feral igs and pythons (etc.) are not going to take over the tundra. Heck... they will be lucky to survive until the end of "summer" if they get out into the wild.
I haven't followed the CITES stuff about green igs. I thought most in the pet trade came from farms and not the wild.
I live in South Central AK, and own a female green ig.