Replacement policy and stuff (9)
I believe the answer is:
substance
'stuff' is the definition.
(thesaurus)
'replacement policy' is the wordplay.
'replacement' becomes 'sub' (I've seen this before).
'policy' becomes 'stance' (I've seen this before).
'sub'+'stance'='SUBSTANCE'
'and' is the link.
(Other definitions for substance that I've seen before include "Subject matter" , "Physical material" , "power" , "Matter or material that a thing is made of" , "wealth" .)