Money earned available immediately (5-4)
I believe the answer is:
ready-made
'available immediately' is the definition.
(I've seen this before)
'money earned' is the wordplay.
'money' becomes 'ready' (ready can informally mean cash).
'earned' becomes 'made' ('make' can be a synonym of 'earn').
'ready'+'made'='READY-MADE'
(Other definitions for ready-made that I've seen before include "Off-the-peg" , "Of standard shape or size" , "Created for standard shapes and sizes, say clothes" , "Prefabricated" , "Of clothes, off the peg, not specially created" .)