Scooby-Doo Where Are You - Spooky Space Kook (1969)
Scooby-Doo was my favourite show as a youngster. At least I remember saying that when I was asked at school, aged about 6.
I don't think it was actually true but I do remember watching it a lot. I also remember wishing that just once, in one episode, that the monster would have been a real monster and not just some bloke in a mask. Not sure that's ever actually happened though.
I could give you the plot breakdown for the episode but it's pretty much the usual. The spacesuit its self is not especially noteworthy but there's a new tag now for 'Skulls in Space' and this is a fine and relatively early example of it.
What is there left to say except he most probably would have got away with it, too, if it hadn't have been for those meddling kids!