UKand Australian
submarines carried Lanchesters and .38" revolvers until the late 60's as we used to overhaul them from the Naval Ordnance Depot in Singapore (I think it was called HMS Terror but don't quote me.....). There were still 6 Lanchesters in the main workshop Armoury when we left in very late 1969 from an ex UK submarine that had been gifted/sold to Australia that presumably left without them!