Just had a look in the garage and have 4 tanwall 700 tubs which would match your 650. They are all new, never been stuck on a wheel, but have all been carefully stored and are is 'as new' condition.
I've got a Wolber Strada 80, a Hutchinson S, a Vittoria Nuovo Pro 260 and a Vittoria Olimpionico. I think the two Vittorias would be the best match. I'm looking for £20 each, plus postage.