I broke down all my mags, cleaned, and lubed them. The one that gave me grief had the top loop twisted to the side, causing the follower to bind up. Someone probably tried to get 15 rounds into the 14 round mag. Five of my mags have no witness holes, and a follower with two round legs in the middle. These hold 14 rounds. They are parkerized with blued bases.
Three other mags have witness holes on the back, and have followers with four corner legs and a round lug under the front of the follower that the spring hooks into. These are also parkerized with blued bases. They hold 13 rounds, and have "Italy9mm Luger/Parabellum". Probably Mec-Gars made for Browning. I know they made the 13 round Beretta 84 mags that had Beretta packaging.
I really need to find my stash of 22 round mags from when I had my first Inglis with a shoulder stock.