Green’s Dictionary of Slang

wink n.1

[? win n.: or resemblance to a tiddlywink]

(Aus.) a sixpence.

[Aus]Baker Popular Dict. Aus. Sl.
[Aus]N. Pulliam I Travelled a Lonely Land (1957) 236/2: one and a wink – one and sixpence (1/6d.).