Aaah, you were referencing G-Zone as a company, not a product. I see.
G-Zone, Ks, Mines, Impul will all do remaps if you ship your ECU to them.
Mines and Impul will even sell you a remapped ECU if you don't want to ship one over (or just want an extra, just in case).
Using FAST with your VIN (which is what you supplied him), I grabbed and PM'd your "Model reference" if that is what he is after.
If he still wants your "chassis number" I suggest you explain to him that the although Stagea is a JDM only model, there are a few examples in the UK... although I always thought that UpRev were a US company.