As I seem to recall, we didn't see too many in original condition as by the time we had them they'd all bee around the block many times. I seem to remember that the Albion made Mk1/1's and 1/2's ones were a wishy-washy grey phosphate and the later Enfield Mk1/1's and 1/2's s were an equally wishy-washy blue/black as you show. Once we'd got hold of them they were black. It looks like yours has got a 52 (1952) stamped onto the body side. Might be worth looking to see what other marks are present. Good tough old pistols and I carried one for several years. But I don't remember anyone winning any shooting prizes with one!