Gold back and large - Liberal with first-class type of desk (4-3)
I believe the answer is:
roll-top
'type of desk' is the definition.
(I've seen this before)
'gold back and large liberal with first-class' is the wordplay.
I cannot really understand how this works, but
'back' could be 'roll' (I've seen this in other clues) and 'roll' is found in the answer.
'first' could be 'top' ('top' can be a synonym of 'first') and 'top' is found in the answer.
This accounts for all the letters.
This explanation may well be incorrect...
(Other definitions for roll-top that I've seen before include "Trollop! (anag)" , "Type of desk" , "Sort of desk" .)