Russ/Anna - Or ask the owners of the one that's just got airborne again:
Drilling Systems (U.K.) Ltd
Hurn View House,
5 Aviation Park West,
Bournemouth International Airport,
Dorset,
BH23 6EW tel 01202 582255
The aircraft is based at Bournemouth/Hurn airport, I believe.
I don't think XN657 is at Lavendon - there's a cockpit at
this museum
but it's not 657. Bits of 657 were at a scrapyard in Essex, but it's been broken up.
The closest to you may be the two Sea Vixens at the
De Havilland Museum by J22 of the M25.