Oh ok. Just read this at Wikipedia:In 1977, Drum Workshop (DW) and Hoshino Gakki (the parent company of Tama Drums) jointly purchased Camco's assets. DW would receive Camco's inventory and manufacturing equipment, while Tama would receive the Camco name, the original design blueprints, and engineering rights.This explains the nearly the same but slightly different lug design plus the reference to the Hoshino badge. Still no clue where the shell were made.
Lots of speculation here on my part, but... This seems unusual, because some of those Tama/Camco drums are clearly Camco shells with re-rings (like the Elvin kit at Maxwell's) - they even have the old badges. Odd that DW ended up with the rights to (and presumably the stock of) the lugs, while Tama clearly got the stock of shells?
Interesting too that shortly after the acquisition, Tama put re-rings in the Superstars... maybe using the "blueprints" for their own high end line, and relegating Camco to "lesser" status, and then a non-entity all together... though the rings in the Superstars didn't last long anyway.
None of this solves where the later TAMCO shells came from - but it would seem either Keller or Tama, both of which are ultimately nice shells!