+1 - I have recently swapped cables and bought them from Mike Larsson. They fitted perfectly. This is a really a wholesaler for allmake workshops but does I think sell some stuff online.
I get mine through a mate with a shop and so saved on post and VAT. But they are cheaper than Triumph.
Throttle control cable for Triumph Rocket 2300 in Cables - standard | Larsson
GET BOTH - Be patient fitting - especially at the engine end.
Nice piccies from the man in a skirt. Show the difference well.