You may want to move this to the 4th gen forum or maybe just the general forum where it will get seen by more people. Or maybe in the UK forum if that is the London you are in.
That said, I'm not sure who can ship to engines to UK or which V6 you have. It looks like Chevrolet Performance sales the 3.8L in various versions.
https://www.summitracing.com/search/...engine-type/v6