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AB... that is a decided possibility. I hadn't thought of an early RAF badge.
From memory alone I can't swear that there are 2 serpents or one. The central
item is definitely not a caduceus, but a well defined ankh. The motto is also worn, but still readable as 'In God we Trust'....somewhat hackneyed, so maybe this was a prototype, later to be changed.
P.S. just spoken to the owner per telephone, who confirms the snake as a singular entity, coiling clockwise around the lower half of the ankh.
ABerrant, I think you've got it. Puzzle solved... I think. My gratitude.