What a fantastic and beautiful piece of synth history. The keyboard in the black and white picture is a Casiotone CT-6000, an instrument I'm familiar with as I own one and enjoy it quite much. Besides being MIDI compatible, its keys are velocity-sensitive and it even has aftertouch. It's a heavy keyboard, with a metal chassis like those of professional synthesizers. Around 14,5kg, I think, similar to a DX7. If I'm not mistaken, this Cosmo Synthesizer was made around 1984 for Tomita, so it makes sense that the CT-6000 would be the controller, I guess.