The cash I had for cover (3)
I believe the answer is:
lid
'for cover' is the definition.
(lid is a kind of cover)
'the cash i had' is the wordplay.
'the cash' becomes 'L' (The pound sterling symbol is an elaborate L).
'i had' becomes 'i'd' (I'd).
'l'+'id'='LID'
(Other definitions for lid that I've seen before include "Cap or top for container" , "Cover for box or eye" , "Movable cover" , "Cover as for jar" , "Cover for box or pot" .)