I can understand your frustration with trying to source parts over there. My cousin used to own a shop in Armadale up on Skye. He would tell me about the delay in trying to get parts.
Before you go throwing any other parts at it. There are a few free things you can try.
I would check to make sure your battery cables are clean and tight on both ends.
Inspect the wiring harness around the back of the rocker cover, The harness can rub thru causing rough idle/stalling.
With the vehicle warmed up at operating temperature, try moving the harness around to see if you can induce a stall.
Wiggle the connectors at the throttle position sensor, IAC sensor and the two connectors at the rear of the rocker cover (one is gray, and the other is black) see if anything happens.
Try wiggling the wiring at the cam sensor and the crank sensor.