The 125 was used by the MD for business trips and even made a few trips to the Caribbean but wasnt flown on charter to my knowledge. It was flown mainly with Dougie White in command.
On other occasions I can recall the late Great Capt John Cunningham
(of De Havilland fame/Comet etc) flying it with Dougie White too?
The Jet Ranger was G-AXMM and the Horizon was I think G-ASJY.
Dave Charity and later others also flew the Navajo G-AYEI on regular crew position flights to Bristol/Cardiff etc.
There was a regular coach service from the North London air terminal in Finchley road that would shuttle passengers from and to London.