A couple allowed a bit of bling (8)
I believe the answer is:
bracelet
'a bit of bling' is the definition.
(I've seen this in another clue)
'a couple allowed' is the wordplay.
'a couple' becomes 'brace' (brace can mean a pair of something).
'allowed' becomes 'let' (to let is to allow or permit).
'brace'+'let'='BRACELET'
(Other definitions for bracelet that I've seen before include "Wrist, arm adornment" , "Ornamental wristband" , "Let caber be made into a piece of jewellery" , "Ornamental band worn on wrist" , "16 [ADORNMENT]" .)