I've got the same revolver. It it an Enfield No2 Mk1. The British service load was called the 380/200. A standard 38 S&W with a 200 gr boolit. In the US this was refereed to as the .38 S&W Super Police. They called the standard 38 S&W load a .380 Rim. Star seems to be the only one offering brass for it. http://www.gunaccessories.com/StarLine/index.asp http://www.grafs.com/metallic/521 I'm holding out for Graf's to get some more in.
Nora