John you are right about the blades, not only that but Merkur makes a detailing beard and mustache razor still to this day that looks exactly like this vintage razor. The only difference other than color is Merkur is German, and mine is made in Japan. I will look into it some more and see if Merkur had any plants in Japan. Thank you for the information.That blade looks an awful lot like the Merkur blades, for size and placement of the holes, and the proportions of the sides.
I would not be surprised if the razor was designed to be compatible with them.