Green’s Dictionary of Slang

penny dips n.

(Aus.) lips.

1967		‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xxxviii 10/1: penny dips: Lips.
1983		R. Aven-Bray Ridgey-Didge Oz Jack Lang 7: ‘What is the ask,’ he said [...] ‘Twenty rugs,’ she smiled showing a couple of Barrier reef missing from between her painted penny dips.