No photos of the inside of the bunker? I wonder what state it's in? That R3 is one of only 2 that we had with EMP proofing (the other was Ash, which we also disposed of), see here:
RAF Ash Now.
I thought £2.5M was a pretty good price (then I remembered the traffic jams in Roy's Town!).
I never understood why they sold it - in my last job secure server storage was a real problem for the Services, but I doubt the MOD would risk buying it back - I can imagine the headlines.
STH