Having just completed some front end work which did involve moving steering from lock to lock a few times, just noticed one of mine is split

Wetness underneath and can easily see the split underneath in n/s gaiter at outer end. Can't remember if KH replaced them when they attended to original leak under warranty, but that was less than 3000 miles ago! These are used on all recent Classics under MMC part # MSR0281 and appear to be of a relatively brittle plastic (or age to such), so not surprising they split.
Have just ordered a pair of universal fit steering rack gaiters from
Car Builder Solutions as suggested further up this thread. Hopefully KH will be happy to fit them if they appear more supple than originals. If not at least I will have spares.