A buddy and me ran discussed this some time ago. There aren't any hard figures that I can find to support any conclusions, but my best guess is that as long as there's a market here in the U.S., the mags will continue to be imported - at least until some congressman/woman &/or senator decides to bar their importation. Of course, that will only increase their value.
I operate under the assumption that as long as I have the money to spend and the opportunity presents itself, I'll take advantage of the opportunity. I've missed that chance too many times in the past to let it slip away now. Hi cap magazines are nearly as good as gold, or maybe even better, when you consider that they're constructed simply of stamped sheet metal or plastic. Tactical value is obvious, too.
Bottom line: the future is uncertain, so don't assume that they'll always be available. And they're a good trading & buying commodity all to themselves.
If you've got the cash, then make your move while you still can. [;)]
[heavy]