Figure to get one for half a dollar (4)
I believe the answer is:
Here is my best explanation:
'figure' is the definition.
(I've seen this before)
'one for half a dollar' is the wordplay.
'one' becomes 'i' (Roman numeral).
'for' says to put letters next to each other.
'half a' indicates taking half.
'dollar' halved is 'dol'.
'to get' is the link.
(Other definitions for idol that I've seen before include "blue-eyed boy", "Billy", "Superstar; graven image", "Object of excessive adoration", "Pin-up", "Greatly admired person", "Worshipped statue", "Image, object of adoration", "Worshipped figure (not painting); revered person" and "Object of reverence".)