Go miles to get a source of best French porcelain (7)
I believe the answer is:
limoges
'french porcelain' is the definition.
(I've seen this before)
'go miles to get a source of' is the wordplay.
'go' indicates anagramming the letters (I've seen 'went' mean this ('go' can mean move)).
'to' says to put letters next to each other.
'a source' says to take the initial letters (source can mean a beginning or origin).
'of' becomes 'o''.
The initial letter of 'get' is 'g'.
'miles'+'g'+'o'='milesgo'
'milesgo' is an anagram of 'LIMOGES'.
'best' is the link.
This may not be right. It may belong to another bit of the clue.
Can you help me to learn more?
(Other definitions for limoges that I've seen before include "French city known for its porcelain" , "French porcelain centre" , "foreign city" , "French commune" , "French city noted for enamels and porcelain" .)