Napoleon, say, receiving message about old fashion item (7)
I believe the answer is:
periwig
'old fashion item' is the definition.
(old-fashioned type of wig)
'napoleon say receiving message about' is the wordplay.
'napoleon say' becomes 'pig' (Napoleon is a pig in George Orwell's Animal Farm).
'receiving' is an insertion indicator.
'message' becomes 'wire' (wire is a kind of message).
'about' shows that the letters should be reversed in order.
'wire' in reverse letter order is 'eriw'.
'pig' enclosing 'eriw' is 'PERIWIG'.
(Other definitions for periwig that I've seen before include "judicial cover" , "Old kind of toupee" , "Old rug" , "18th-century hairpiece" , "topping" .)