Contribute two fifties and get round for artist (9)
I believe the answer is:
donatello
'for artist' is the definition.
(I've seen this before)
'contribute two fifties and get round' is the wordplay.
'two fifties' can mean two replacements for 'fifty'.
'contribute' becomes 'donate' (I've seen this before).
'fifty' becomes 'l' (Roman numeral).
'fifty' becomes 'l' (Roman numeral).
'and' is a charade indicator (letters next to each other).
'get round' becomes 'o' (I've seen this in other clues).
'donate'+'l'+'l'+'o'='DONATELLO'
(Other definitions for donatello that I've seen before include "Chipper" , "Italian artist" , "Famous Florentine sculptor" , "C 15 Florentine sculptor" , "Italian sculptor" .)