Dispute burying a Republican charge (6)
I believe the answer is:
tariff
'charge' is the definition.
(I know that tariff is a kind of tax)
'dispute burying a republican' is the wordplay.
'dispute' becomes 'tiff' (tiff is a kind of dispute).
'burying' indicates putting letters inside.
'republican' becomes 'R' (abbreviation in US politics).
'a'+'r'='ar'
'tiff' enclosing 'ar' is 'TARIFF'.
(Other definitions for tariff that I've seen before include "Duty; table of charges" , "Import duty, tax" , "List of customs duties" , "Duty charge" , "Table of fixed charges" .)