Chase popular copy in Home Counties (8)
I believe the answer is:
inscribe
'chase' is the definition.
(chase can mean to etch or engrave)
'popular copy in home counties' is the wordplay.
'popular' becomes 'in'.
'copy' becomes 'crib' (I've seen this before).
'in' is an insertion indicator.
'home counties' becomes 'se'.
'crib' inserted into 'se' is 'scribe'.
'in'+'scribe'='INSCRIBE'
(Other definitions for inscribe that I've seen before include "Write or cut words into a surface" , "chase" , "Engrave; dedicate" , "Write a dedication to someone in (a book)" , "Scratch" .)