I've gotten mine through friends and off eBay.  HobbyLink Japan is a good choice, especially if you're concerned about avoiding recasts.  I can't say anything about the kits, but many of the figures that you'll see on eBay are recasts.  Some are labeled as such (there's a seller in Hong Kong that lists them that way), others aren't.

If you guys up there in the Great White North have Asian malls, with their own hobby shops, well, beauty eh.    We have instead malls with Chinese restaurants in them, that sell no kits.

There is also a forum dedicated to Maschinen Krieger, http://maschinenkrueger.com/forum/ and you might want to check it out.  Some members here are members there, too, and I think you'll be able to find more info on those boards, on where to find MaK kits

Hope that helps!

Brad