I've got a spare wheel from my old 250 Cup that had been hidden away in the garage for the past few years. https://photos.app.goo.gl/NUxX7DZMvvX7iKSY8 It's in nice condition (See pics for full details!), it was resprayed a few years ago. The tyre is a very old Eagle F1 and I wouldn't really suggest using it anymore, but it does have some tread. I live near Cardiff but work in Bristol a few days a week so you could meet me near my office in central Bristol or I could meet you along the M4 between there and Cardiff.
Sorry only just saw this. I wasn't planning to post it to be honest, it's heavy and I fear it wouldn't arrive in great shape, hence saying I'm happy to meet someone near Cardiff or Bristol for it