Travelling salesman set up rural department stores (6)
I believe the answer is:
pedlar
'travelling salesman' is the definition.
(someone peddling their wares)
'up rural department stores' is the wordplay.
'up' says the letters should be written in reverse (in down clue: letters go upwards).
'stores' indicates a hidden word.
'raldep' can be found hidden inside 'rural department'.
'raldep' back-to-front is 'PEDLAR'.
'set' acts as a link.
(Other definitions for pedlar that I've seen before include "Travelling merchant" , "Itinerant vendor" , "Mobile salesman" , "Travelling seller" , "Person who sells door-to-door" .)