TonyT
Thanks for clarifying.

Tangmere 1940
Thanks for posting – the plot thickens!
I looked up S. F. Soden on the internet and all reports say that the plane he baled out from on Oct 25th 1940 was Spitfire P7635. Is it possible you made a mistake with the number in your post? The reason for asking is because I plan to mount the assembly on a plinth (for my own benefit) with a note on the possible Spitfire sources.

From everyone’s input I’m confident that this part is from a Merlin engine which in turn means that there’s no reason for me to doubt the ebay listing description of it being from P7309 (or possibly P7635 due to the reason given by Tangmere 1940).