Naval Police.
As previously mentioned, the Naval Dockyard Police were established in 1913 and then renamed the Naval Police in 1972. In 1991 they were amalgamated with the Coxwains to become the Naval Police Coxwains (NPC).
The original buttons featured the Tudor Crown, used during the reigns of Kings Edward VII, George V, Edward VIII and George VI. After her coronation in 1953, Elizabeth II used the St Edward’s Crown. For examples of the buttons with the backmark “Stokes Melb”, see http://www.austbuttonhistory.com/14th-june-2022/
Today I have two new variations with the St Edward’s Crown . One has the backmark Stokes & Sons Victoria (i.e. 1953-1962, after which the manufacturer became Stokes (Australasia) Ltd).
The second button has the backmark Stokes Australia; the design has changed, with an upright anchor and the words “Naval Dockyard Police” dropped.
Perhaps these date from 1972 onwards when they became a part of the Navy proper, rather than an auxiliary, and were renamed the Naval Police. They were sold as Vietnam War era (1955-1975) Naval Dockyard Police buttons, so this would fit. It is the same general design used by the Royal Australian Navy, but white-metal rather than gilt.
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