If you decide to re finish the frame, it would be interesting to see it when it's finished. Also I don't feel Chas Roberts are doing themselves any favours, saying it's not worth repairing, unless it is badly damaged of course. Their frames are not cheap and the whole idea behind a custom steel frame, is you can have it repaired and re painted. Bob Jackson will replace any tubing for you at reasonable money.
It defeats the object rather, you may as well just buy a cheaper ally frame and throw it away after a few years of hard use.
I have just rebuilt a 14 year old Orange CR16r and it's better than new, as I have up graded a lot of the running gear to XT, or better. Despite the age, it has no rust on it. You could have a go yourself, strip with Nitromors first then a good going over with a Phosphor bronze brush finish detail off with a Dremel and a phosphor bronze brush. A thin coat of anti rust primer then away you go with whatever finish you fancy?