I don't know, but the ban isn't on buying per se, it's on selling. Manufacturers and retailers (if there were any newly manfacturered guns and/or magazines other than LE only) are not going to risk losing their licenses in order to be a test case. From the gun grabbers point of view, that's the beauty of the law, no one to take it to court where it just might be found unconstitutional.
Oops again, it's on both, but otherwise the comments still apply. It's hard to buy something that no one will sell.