Box delivered in Raynes Park (4)
I believe the answer is:
spar
'box' is the definition.
(I know that spar is a type of box)
'delivered in raynes park' is the wordplay.
'delivered in' indicates a hidden word.
'SPAR' is hidden within 'raynes park'.
(Other definitions for spar that I've seen before include "have an argument without marked hostility" , "Mineral; strong pole" , "Crystal - box" , "Translucent mineral" , "Box in training - nautical pole" .)