Mag-Pak Magazines - 8 round cap.

Does anyone have a source for Mag-Pak magazines? These mags have a ball bearing within the follower for smooth functioning. I have found these mags are the only mags that you can load empty cases into and have them feed ultra reliably. (Which translates to great functioning with all types of ammo reguardless of throating) They are fantastic mags, (above and beyond most all 1911 mags) but are hard to come by. If I recall, years ago, when J. Cooper was still at Gunsite, they made a 1911 which used these mags. I have tries Brownells with no luck. I found a website (Westernmills.com) where they sell mag-paks but only for the officers model. Im looking for standard Govt. size (8 round) mags. Can anyone help??