Shelf with right sort of book (6)
I believe the answer is:
ledger
'sort of book' is the definition.
'shelf with right' is the wordplay.
'shelf' becomes 'ledge' (synonyms).
'with' is a charade indicator (letters next to each other).
'right' becomes 'r' (common abbreviation).
'ledge'+'r'='LEDGER'
(Other definitions for ledger that I've seen before include "In which accounts are entered" , "Book-keeper's book" , "Old accounts book" , "record-holder" , "Accounts journal" .)