Hi there
I posted a similar request a while back, but nobody came forward. I think good distributors are hard to come by as most are on cars and spares are generally worn. If you call Derek at Renospeed, he will sell you a second hand one if he has one. He didn't have any when I last spoke to him and I don't think they turn up very often. I couldn't hang around and wait, so I ended up buying one from Windclassics. This was an expensive option, but for me it was well worth it. The car has a whole new lease of life and runs like a dream!
Good hunting!
Chris