Update:
Looks like Larry had been fitted already with a Sanden compressor.
This is the bracket.
The compressor site where the alternator usually does - here is a picture of the engine bay of Xoe the 74 142 without air - note position of alternator and the mechanical fuel pump.
Here is the corresponding position on Larry, the 73 144 with air. Note the compressor bracket has been removed so I can get to the fuel pump (AKA the bane of my life at present). The (extremely dirty) Sanden-type compressor can be seen in the lower left of picture.
(I am not certain if it's actually a Sanden or not; I am going to give it and the engine a 'Madam Helicopter Bath' before heading south).
Here's a BNIB (or BNJOOB / Brand New Just Out Of Box) Sanden 4664, which is destined to replace the dead one on The Cleever.
And as can be seen, the bracket lines up with the Sanden compressor.