Call about one republican being less genuine (7)
I believe the answer is:
phonier
'less genuine' is the definition.
(I've seen this before)
'call about one republican' is the wordplay.
'call' becomes 'phone' (phone can mean to call by telephone).
'about' is an insertion indicator.
'one' becomes 'i' (Roman numeral).
'republican' becomes 'R' (abbreviation).
'phone' placed around 'i' is 'phonie'.
'phonie'+'r'='PHONIER'
'being' acts as a link.
(Other definitions for phonier that I've seen before include "Less genuine" , "More affected" .)