Suitable pen-friend? (13)
I believe the answer is:
correspondent
I believe this clue is a double definition.
'suitable' is the first definition.
(corresponding or comparable)
'pen-friend?' is the second definition.
(someone you write letters to or correspond with)
(Other definitions for correspondent that I've seen before include "Pen-friend" , "Journalist; letter writer" , "Reporter on special subject or from overseas" , "Person sending letters or written reports - agreeing" , "Reporter on specialist areas" .)