The caliber is making a comeback. Glock makes the G20 in 10mm and a smaller version. Bunch of S&W 10mm's still around, and they are now making a revolver.
The Bren 10 is being re-introduced. Still a bunch of Colt Delta's around.
I have a S&W 1076 that is a great gun, which was the model used by a bunch of law enforcement. The FBI liked the caliber, but it was too "heavy" for some of their smaller statured lightweight employees.
Ammo is around, but pricey. About the same price range as the .357 Sig.