Since getting hold of fashion label, swan around East End in denim headgear (9)
I believe the answer is:
cockscomb
'headgear' is the definition.
(cockscomb is a kind of headgear)
'since getting hold of fashion label swan around east end in denim' is the wordplay.
I cannot quite see how this works, but
'of' could be 'o' and 'o' is located in the answer.
'around' could be 'o' (a round letter) and 'o' is located in the answer.
'fashion label' could be 'ck' (Calvin Klein) and 'ck' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for cockscomb that I've seen before include "Capital feature of bird" , "one that makes a crow" , "Bird's crest" , "Crest on domestic fowl" , "Rooster's crest" .)