Lat time I asked them for things like the points plates, crank/rod bearings (which fit many bikes, they are from a Mitsubishi car engine after all), their pistons and rings (but RIK and MC make their rings), and handlebar switches. They would not respond about pipes and tanks, but I think Yamiya has a handle on those. I asked them for all the SOHC4 bikes' parts (even for the 250F, which Sochiro built just for the Japanese).
In typical Japanese fashion (which I learned from working with them between 1972 and 2008 in various industries) they selected the last item of the list that they accepted and would consider: I purposefully made this item the points plate assemblies so they could accept the whole list in a single statement. I got back from them the ACK that they would look into supplying [up to] the last item. That was in October, 2020.
Does anyone know of a place on the 'net where we could put up a 'petition list' or maybe just a list of those in support, so I could send them a link to it? I'd then craft the same letter again. I don't want it to get 'cold'.