Restoration novel in authentic setting (7)
I believe the answer is:
renewal
'restoration' is the definition.
(synonyms)
'novel in authentic setting' is the wordplay.
'novel' becomes 'new' (synonyms).
'in' means one lot of letters goes inside another.
'authentic setting' becomes 'real' (I can't explain this - if you can you should give a lot more credence to this answer).
'new' put inside 'real' is 'RENEWAL'.
(Other definitions for renewal that I've seen before include "Replenishment" , "Modernization" , "Act of refreshing" , "Continuance" , "Restoration, recovery" .)