Well, it may not be germane to the discussion at hand, but I converted several 5.45 Russian balelite AK mags (that I bought cheap from the US) to fit/function in my Galil ARM without too much drama. For the most part, they simply required that I thin out the bakelite on the upper surface of the feed-lips (no big deal - they are steel under synthetic), and then reduce the locking lug's lower surface a few thous. That was it.
The thing is, that the case geometry is fundamentally different between the 5.56mm NATO and the 5.45 Russian round. They are compatible (but not ideal) at the Canadian-legal 5-round mark, so no problem for Canuck shooters if you can find the Russian mags (suitably pinned, of course). If our laws governing the use/possession of factory-standard capacity magazines were realistic however, you would find that the 5.45 AK mags would not accommodate 5.56mm ammuntion beyond the 12 or 13 round count. The different cartridge case geometry causes severe follower-binding at that point.
Just something I was told from a reliable friend in the US. For what it's worth...