It won't happen. The "Save Concorde Group" are a bunch of dreamers, the 593 lot the French equivalent.
There are no parts, there's no certification, no support (Airbus say "Non!"). The CAA won't allow it. No-one will pay for it.
Look how hard the Vulcan guys had to work to get their comparatively simple, subsonic bomber to be allowed to fly under massively tight regs (VFR, etc). And that's an ex-military a/c that
never needed original approval/certification. Concorde would be 10000x more complex, and impossible to certify. The CAA wouldn't want a supersonic a/c in the hands of "enthusiasts".
Furthermore, aside from one tucked away in a museum, all
the a/c have had their hydraulic systems drained and disabled. With 7 years of no maintneance,
they're dead aircraft.