Pair allowed item of jewellery (8)
I believe the answer is:
bracelet
'item of jewellery' is the definition.
(I've seen this before)
'pair allowed' is the wordplay.
'pair' becomes 'brace' ('brace' can be a synonym of 'pair'**).
'allowed' becomes 'let' (I've seen this before).
'brace'+'let'='BRACELET'
(Other definitions for bracelet that I've seen before include "Jewellery -- clear bet (anag)" , "Jewellery worn around the wrist" , "Let caber be made into a piece of jewellery" , "Wrist, arm adornment" , "Ornamental band worn on wrist" .)