I know this post isn't strictly a problem or question or technical but I do know folks with SPI's seem to be looking for spares or replacement Throttle pots...there's one currently for sale on Ebay. Not cheap, but it wouldnt be, but someone here might want one.
Didn't seem right to put it in the 'for sale' bit either but feel free do to so if that's the best place to put it.
Genuine Rover Mini Metro 100 200 Throttle Potentiometer Pot JZX2962 RARE
https://www.ebay.co....dffff10ee|iid:1