Amazon just turned it up:
https://www.amazon.com/Uchu%C3%8C-ka...=9784898298275
They list the author as Reiji Matsumoto, which is a very, very familiar name. I'm sure I've seen in in the last couple of months while I've been digging for info.
What amazes me is that PMI (or for that matter, Hathaway) never picked up any of the Japanese models I've found, particularly not these 2 from Wani magazine. Or any other Japanese models.