Just an update for anyone thinking of ordering these. I received two, which appear to be in new, unissued condition. However, other than the "CZ MFG" stamp on the baseplate, they are unmarked. No crossed swords. They have a welded seam down the center of the back which is a little bit "flexible", in that it feels like you could crush it with a good squeeze at that point. However they do seat perfectly in the mag well, eject, and operate the slide stop when empty just as well as the original CZ mags I have.
I suspect that these are from a military contract buy by some country that issued the CZ-82/CZ-83 - from the "lowest bidder, so to speak - but that they may work perfectly well. (As a side note, our own supply people screwed up with a big Beretta 92 mag order from Mec-Gar when some rear-echelon weenie insisted that Mec-Gar phosphate coat the INSIDE of the magazine tubes. Once they hit the sandbox our soldiers found that they wouldn't feed reliably until they stripped them down and polished the phosphating off of the inside of the tube.)
I loaded up the two that I have, one with S&B and the other with WWB with the flat point. I received a Caldwell chronograph from Santa that I want to try out (We were experiencing unprecedented monsoon weather around Christmas, but now it's gone to sunny and cold), so today I may set up down in the back yard by the creek and blow through the WWB to see if my CZ83 will feed it, and see if the mags work.
I probably won't use either of these as carry magazines - just due to my nagging lack of confidence with them - but will relegate them to range mags (at least for the foreseeable future).