G'day Llew,
Bruce has a Tecumseh bowl listed over at the ODK Shop that might suit; the bowl is a 'common part' used on a number of different Kirby and Tecumseh engines.
He may need accurate measurements of a few dimensions, to confirm it's the right part, so it's best to contact him through the Shop website; the bowl is on this page;
https://www.outdoorking-forum.com.au/engines...h-carburettors-parts?sort=20a&page=3 BTW, that bowl doesn't have the drain valve, which is a plus - no rubber seal, which eventually perishes and leaks fuel.