I'm currently servicing a n early one with the separate medallion in brown grip. It does have slight deformities around the 4 screws in the grip, but no cracks. I've never heard of an end cap coming out as there's about15mm of thread involved, plus a locking grubscrew. To be fair I've only ever had to work on a couple in 50 years of experience. Oddly I own one, which wouldn't cock, so I fitted a new sear, nothing else is faulty but it still won't cock ??? so it sits in a drawer with other ''odd'' models. Good luck with your search, I confess I now know more of it's history and variants, as I'm not that much informed on this pistol.