Bowden Cable.
 

Supplier wanted for Bowden cable as used on vintage commercial brakes. Many thanks, Neil Smith.

There is a specialist cable supplier at Lighthorne in Warwickshire , who do cables for cars , motorcycles and all such tack . I shall try to remember their name , but I fancy that it is something unremarkable like Johnson or some such . Try a Google .

Now trading as JJ Cables , Lighthorne according to google . They should sort you .

Despite having a surname of Bowden I do not supply Bowden Cable. On a more serious note, it is good to hear of someone calling this type of what in effect is quite a common type of cable by it's proper name instead of, for example, a brake cable for a pushbike.

I have used this firm in distant past when having cables made for a Cayton Dewandre vacuum braked trailer.
http://www.speedycables.com/cables.html
formerly London now based in South Wales.