Lobo, Those were ordered by South Africa and S&W shows shipping to S.A. in 1940 but it seems as though the first couple of shipments were rerouted to other British Commonwealth uses (British proof marks). Found this out when I was researching my first one (the one on my Trio thread with the U arrow and property #). So far I don't think anyone has actually found any paperwork to answer the who, what, when and where this happened but strong circumstantial evidence dictates this was the case.
One of the things I like about these revolvers is that they have a wild story behind them but are not so wild that I can't go have lots of fun shooting them. Hope you enjoy yours as much as I have mine.
Larry
P.S. Hope Midway get Brass in soon for these. 150 cases dont go far in a days worth of fun.