Said to be a sale of cloth (4)
I believe the answer is:
sail
'cloth' is the definition.
(sail is a kind of cloth)
'said to be a sale' is the wordplay.
'said to be' indicates a 'sounds like' (homophone) clue.
'sale' sounds like 'SAIL'.
'of' acts as a link.
(Other definitions for sail that I've seen before include "Spanker, say" , "Go by boat" , "Spanker or spinnaker, for example" , "Travel on water propelled by wind" , "Go by water" .)