Edit:
...a HUGE "thank you!" to
bestmajor, whose unflagging efforts in searching missing aircraft models resulted in the finding of a drawing (even in color!) for the almost-not-to-be-found
Kugisho Tenga, a late WW2 Japanese jet naval bomber project.
This let me complete Japan's aircraft icon set by making that last missing icon. His deed is worth a screenshot of the ensuing work that has been possible thanks to his finding, plus a special release of the Corrections file.
If there would be some three or four clones of bestmajor, I think there wouldn't be anything the modding community couldn't do...