Traveller's passage -- cost of passage ending in Dover (8)
I believe the answer is:
wayfarer
'traveller's' is the definition.
(wayfarer is a kind of traveller)
'passage cost of passage ending in dover' is the wordplay.
'passage' becomes 'way' (I've seen this in another clue).
'cost of passage' becomes 'fare' (eg a train fare).
'ending in' indicates one should take the final letters.
The last letter of 'dover' is 'r'.
'way'+'fare'+'r'='WAYFARER'
(Other definitions for wayfarer that I've seen before include "One journeying on foot" , "Bird of passage" , "Trekker" , "Person on a journey - sailing dinghy" , "Person who travels on foot" .)