In the IPC this stud 561886 appears as the serrated alternative to the threaded 561590, which is too short & I'm sure is the one I have on my hub. Counting the turns & translating those to the serrated area gave me the impression it might have been longer.
I hoped the vendor would have measured them for me. Although they are more expensive than other dealers, if he has gone to the trouble of taking pictures for his advert & hopefully answering my questions, I was going to buy from him. In the same way if a shop is prepared to give me advice on a product I will buy it there rather than sneak of to buy it on-line where there a no such staff or overheads.
I have looked at Philip's stock list & did a search for "studs" (no funny comments please) I wrote down the part numbers for them all & did searches to find out what they were. I didn't unearth anything that was eligible.
Originally I was thinking of a complete hub, but as hopes for that faded, spurred on by the cheapness of studs I was drawn to changing them myself. But it is just so frustrating not being able to identify a part number.