British Police Mk II. Original? Based on dates (1939 on liner, no date or covered by chinstrap Swivel on the steel) very early war, Battle of Brittan era. This is all I know of this one. What is the rarity of this and what is the value. (We paid 7 and a half pounds for it at a small shop in Ipswich England in the late 70s) Any additional info would be great.