I can not find a "Magnetic Oil Drain Plug" for the Jaguar XK8.

Why:
Powerful magnets embedded in them so they catch any ferrous metallic particles that might be scraped from cylinder walls or from gears, etc Clean metallic particles off next time one drains the oil.

Where can I get one, please?

I do not have a tool to measure but I would need to know the size to purchase.

Thanks!