Toyokawa "Rocking Star" Type 30 Bayonet

This specific bayonet has black-painted handle parts but the blade looks like it was crudely blued a long time ago. The left grip panel is faintly stamped with kanji which translates to "substitute." There are no markings on the pommel or tang. The grip panels are attached with rivets and oval washers, and the blade is completely unsharpened.

I cannot seem to find any information about this specific variation of bayonet, and it is not listed in LaBar's book. Does anyone know if the Japanese Navy blued their bright blades to match the painted handles? Any additional information would be greatly appreciated! Thanks in advance!