Can't lire be exchanged for an instrument? (8)
I believe the answer is:
clarinet
'an instrument?' is the definition.
(clarinet is a kind of instrument)
'can't lire be exchanged' is the wordplay.
'be exchanged' is an anagram indicator.
'cant'+'lire'='cantlire'
'cantlire' anagrammed gives 'CLARINET'.
'for' is the link.
(Other definitions for clarinet that I've seen before include "Find an instrument in claret" , "Blow that!" , "Musical wind instrument as played by Benny Goodman" , "Woodwind instrument played by Artie Shaw and Benny Goodman" , "Instrument in claret, strangely" .)