I am looking at an S&W .38 specialwith 5 inch barrel, 5 screw frame (4 on the sideplate and one in front of the trigger guard.) with fixed sights, double action, and diamond decorated stock with S&W script stamp marked side plate which has a serial number in the 12XXXX range without any model information anywhere. There is a build number behind the cylinder crane, but no model number is there as in more recent models. I know it to be quite old and with law enforcement background - runs in the family. Trying to learn the date of shipping from S&W.
Is it properly considered a Hand Ejector model, Regulation Police, 1905, or Military and Police?

Thanks in advance!