If anyone is hunting the plugs and sockets making up the various components in the ignition system, they are JPT connectors, aka Junior Power Timer.
They can be expensive,. It can also be bought at a more reasonable price from AliExpress.
In regards to the Hall Effect tester, I have greatly simplified the circuit by using 12v LED panel lights, this eliminates the resistor. I have also deleted the switch and put the LED into the back of a JPT socket. I feed power externally from a 9v battery - having it out in the open reminds me to disconnect it.