Well I will try to answer my own question and seek confirmation. The proof marks are British. Birmingham proof. I think it was proved as a 9mm MS with a 245 grain bullet. I am not sure of the the rest of the proof info. Any help appreciated. Any idea as to date? 2.22? the Crown over BNP info I have shows that mark first used in 1954.

Any ideas about the express sights and or British maker or retailer? Thasnk you.