Quality of pun from Republican (7)
I believe the answer is:
calibre
'quality' is the definition.
('calibre' can be a synonym of 'quality')
I can't explain the remainder of the clue.
Can you help me to learn more?
(Other definitions for calibre that I've seen before include "gifts" , "weapon's bore?" , "bore on the Tube?" , "Personal character" , "Diameter of bore of firearm" .)