I was looking for some other stuff when stumbling across these clips from Majin Vander, a toku show from 1969 produced by Nissan Pro who 10 years earlier had done Marine Kong.
Apparently this is based on a by Osamu Tezuka and there was also an anime, though I haven't found much about that.
Well, suffice to say I'm a magpie for weird, obscure, hard to find shows. It doesn't seem to be on DVD, but if anyone happens across any episodes, please let me know! I did find the and I'm guessing (which doesn't seem to have the robot in it at all) but hope there exists somewhere better copies of all 13 episodes.