I dont think anyone has mentioned tactical airsoft and milsim magazine yet... Its out of the U.S., I have a subscription, and I find it an excellent publication. I was e-mailing Steve Kerry a while back regarding an irregularity in my subscription, and he went out of his way to personally rectify it for me. I learned that they're revamping the publication, and he said to wait before purchasing my next subscription, as they expect it to be cheaper in the coming few months.
Link:
http://www.tacticalairsoftmagazine.com/
And yes ShortCut, you can get N.A.M. magazine across the border. I bought an issue quite a while back, and received it no problem.
Hope that was helpful
Swalsh.