The badge in question makes me think of the Aussie sunburst badge. At least you bumped the thread for others to see.
P&O had something similar on their uniforms, I think. No idea if this is the same, but it does look nautical I guess.
I have tried to match it to some form of headress. It seems to me to be a 'sunburst' of feathers arranged on a turban type cap. The base looks similar to the headress worn by Zulu and other South African warriors. I was thinking of the Colonial troops who served in the Pioneer Corps and some AA gunners - Basutos, Swazis, Bechuanans etc. Long shot!
I saw a tank. But on closer inspection I think some threads have come loose. Edit: On a sensible note just found this after seeing James' clue. Shipboard Organization and Stewards P & O Catering Petty Officer.