Mate providing money for pop (3)
I believe the answer is:
pal
'mate' is the definition.
(I've seen this in another clue)
'money for pop' is the wordplay.
'money' becomes 'l' (L can mean 'pounds').
'for' says to put letters next to each other (I've seen this in other clues).
'pop' becomes 'pa' (both can mean father).
'l' put after 'pa' is 'PAL'.
'providing' acts as a link.
(Other definitions for pal that I've seen before include "Crony" , "Mate, buddy" , "Brother" , "Bud" , "Buddy, chum" .)