The 9mm in both barrel lengths was discontinued around 2000 but then reintroduced only in the 2.25" barrel a few years ago. So all of the 3" guns (model KSP-931) were from the earlier production. There are no estimated quantities that I can see but the RENE Ref lists production being in the 570-26480 to 572-89010 serial range.
Interestingly, the high polish GKSP-931 is listed, complete with a numeric model 5730, but none are known. And only two known examples of the 2.75" high polish GKSP-921.