If you find a source, list it here with all the info you can, links, description, price, part number etc.
John F at Woodnstuff sold his business to Jim Calder (http://www.justliveoffgrid.com/)
I have had the pleasure of dealing with him many times. Good prices, reasonable shipping. He stocks items not listed on his website,
or can get for you if you are patient.
Here in Canada Jim is a good go-to for parts and engines.
Cheers,
Hugh
Central Maine Diesel
http://www.centralmainediesel.com/
(207) 941-1188
They stock a lot of Metro Listeroid parts, I have bought a number of parts from them over the years for my 2 Metro 6/1s. Always prompt and courteous.