Broken stapler needs cover (7)
I believe the answer is:
plaster
'cover' is the definition.
(I know that plaster is a more specific form of the action cover)
'broken stapler' is the wordplay.
'broken' indicates an anagram.
'stapler' with letters rearranged gives 'PLASTER'.
'needs' is the link.
(Other definitions for plaster that I've seen before include "Render (walls)" , "Daub" , "Spread" , "A paste; a dressing" , "Smooth covering for walls and ceilings" .)