Metalform mags are available from Brownells, or direct from Metalform. I am using one of their Combat Master, and two of their 1911-length 7-round magazines in my CM, and they all work great. The mainspring housings were made by Pachmayr, and I think they're still available from Brownells; it's a standard 1911 part. Mine has had some material ground from the top, just above the pin hole, which looks like clearance for the sear spring. I'm using King's recoil springs. They make a two-spring set for their Officers ACP recoil guide rod kit, and they are just the right length and rate for the CM. Call King's, and ask for a set of replacement springs. I think they're $8 per set. Wolff makes a single spring that is supposed to replace the factory double. I have one of these, but haven't tried it yet.