If neither Paul or Duncan want to tackle it I would be very wary about handing it over to any well meaning amateur. I had Duncan repair & service an Omega 321 Speedy for me and, as part of that job, he had to ‘manufacture’ at least one unobtainable part, so I know that he has the tools and the skill set. If he has declined the task there’s likely a very good reason.
The one suggestion I would make is to contact Brendan Hoey, Torquay, webwatchmaker.co.uk. He will certainly be worth a try.