Stefan, Glad you got a chance to see that ebay listing. The real answer to the identity of the guitar I believe was under the soundhole label the dealer had applied. I did send a note to the seller asking if he could see any clue of a stamping. He said he would look and get back but that didn't happen, no surprise. He also did not post my question. There is a very good chance the new owner uses this forum, so we may find out in due course.
Look forward to news of the database, a good idea.
I also am interested in MIJ guitars.
I have 4 Hohners, 3 Suzuki's, 1 Aria, all acoustic. I have 2 acoustic and 1 electric telly copy NORTHERN brand guitars that were made in japan for the Canadian market, info on these is virtually non existent. They are easily identified by the maple leaf on the headstock. My best guess is Hoshino made but I think the electric could be Tokai, high quality stuff.
My DR-7 is MINT and my best player.
My 65 Harmony Rocket and 66 Harmony Bobkat, and Seagull SM12 round out the collection.

My other Japanese collectible is my 1977 Toyota Celica GT Liftback.
Check out collectiblecars.nytimes.com
I search from time to time for Toyota guitars cause they are out there but no luck so far. Be nice to throw one in the Celica for fun! Cheers Neil