I have two pairs of UK spec (low bar) throttle cables, part numbers 17910-323-620 and 17920-323-620, which are no longer needed. Both sets are genuine Honda parts, not pattern, and have been stored in the house for at least 20 years now:-
One set is NOS still in original sealed packets - £25 inc. post
The other set was fitted to our 1971 K0 briefly (maybe 200 miles) before I re-fitted the correct US spec high bars along with the necessary longer cables. As good as new, with perfect chrome end fittings - £20 inc. post.
Chris R.