Choice era for feathers (7)
I believe the answer is:
plumage
'feathers' is the definition.
(I've seen this before)
'choice era' is the wordplay.
'choice' becomes 'plum' (both can mean excellent).
'era' becomes 'age' (both can mean a long period of time).
'plum'+'age'='PLUMAGE'
'for' is the link.
(Other definitions for plumage that I've seen before include "Birds' clothing" , "Cover for diver" , "A bird's feathers, may be fancy" , "coat" , "One's feathers" .)