Sorry Musky but those pegs are defo more scarce than rocking horse sh1t ,I tried for some 6 to 5 yrs ago and gave up and then not having your engineering skills, I looked at the prob which in my case was that when tightening I was actually pushing the footrest off the spline which then allowed the footrest to slip by putting a large lump of brass behind the footrest and the frame I managed to stop the slip .From memory it was a cut down fork bush which fitted the footrest perfectly ,cant see it unless you get on the floor and is still ok yrs further on .Just a thought cheers for now