rodthesod: that's a new one on me, reheat Avons in a Meatbox !
I would be happy to be corrected, but it sounds like the product of someone's imagination.
There was a research Sapphire engined Meteor that held some climb records at one point, but to the best of my knowledge, never one with Avons.
The aircraft that Zura did the cartwheel in was, as Bof pointed out, a pretty standard Mk8, but with a load of rockets slung under the wings towards the tips.