Unfamiliar look for Welsh composer (7)
I believe the answer is:
novello
'welsh composer' is the definition.
(Welsh composer Ivor Novello)
'unfamiliar look' is the wordplay.
'unfamiliar' becomes 'novel' (novel can mean new or unfamiliar).
'look' becomes 'lo' ('lo' is an archaic exclamation meaning 'look!').
'novel'+'lo'='NOVELLO'
'for' is the link.
(Other definitions for novello that I've seen before include "Ivor --, songwriter" , "popular composer" , "See 8" , "he used to make up the numbers" , "Ivor --, Welsh singer, actor, composer" .)