Thanks for the details, Chris, but you have the complete pot - it's just the outer that's needed, having found an old CI inner lying around. It would be a shame to separate what looks like the really nice unit that you have.
Reason for looking to use the "found" pot is that the existing smaller pot for use on restoration jobs is JUST too small to sit stably on the camping gas stove used to heat it. So a slightly larger unit would be safer. It seems a waste to be heating up the large amount of glue needed to cover the base of the ancient (and definitely not PAT tested!) electric one when only a small amount is needed. Probably doesn't do the glue any favours, either.
Will keep hunting, or possibly try a bit of metal spinning one day, but thanks again. If a suitable outer turns up, the current smaller pot may be for sale; then again, having three possible sizes of pot could be useful.
A "collector"?? Moi??