My frustrated response to Evri seems to have worked and my quilting foot might be delivered today.
This is the "bodge" to get the remote working:
The Foot control on my new sewing machine is operating at 5V DC so I do not need a high voltage insulation to make an adapter. First shape up some Nylon to match the HD9's connector and check the pins all line up:
Then add a bit of cable, brass pins soldered onto the machine end of the wires, slide some sockets onto the pins on the remote's pins, apply heat shrink between all wires for insulation and as a cable protector and one adapter cable:
And it works so that is £85 saved
Please note: I did a 4 year Electronics apprenticeship so I do know what I am doing fiddling around with electrics. If you don't have the experience/knowledge please do not fiddle with it. Especially with older machines which have 230V AC wiring to their foot controls.
Jo