First-rate raffle in boozer (3-6)
I believe the answer is:
top drawer
'first-rate' is the definition.
(I've seen this in another clue)
'raffle in boozer' is the wordplay.
'raffle' becomes 'draw' (a prize draw).
'in' indicates putting letters inside.
'boozer' becomes 'toper' (both can mean someone who drinks a lot).
'draw' put inside 'toper' is 'TOP-DRAWER'.
(Other definitions for top drawer that I've seen before include "Highest social position - or sliding furniture box" , "such as da Vinci?" , "Of the highest class" , "Highest level of society" , "high-class" .)