Jack provided fellow's price list (6)
I believe the answer is:
tariff
'price list' is the definition.
(I've seen this before)
'jack provided fellow's' is the wordplay.
'jack' becomes 'tar' (I've seen this before).
'provided' becomes 'if'.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'tar'+'if'+'f'='TARIFF'
(Other definitions for tariff that I've seen before include "Import/export tax" , "Fees schedule" , "Sentencing scale" , "Tax or duty on a class of imports" , "Customs duty" .)