Very cool, rather reminiscent of the Unicorn uniforms from Johnny Sokko/Giant Robo. The problem that you're likely to run into, one that I did researching the Unicorn costumes, is that references pics are hard to come by online and what you can find ten to be pretty small in size.
The base costume looks relatively simple to make, it would be mostly a matter of finding the right type of fabric in the right color. Chances are, since it's from 60s or 70s the fabric is some kind of polyester and you can either sew a dress shirt directly to the jacket or make a fake shirt from the same or similar material as the jacket.
The helmet looks like an old vinatage motorcycle helmet with a visor and greeblies on the ears. The helmet you can find online although pretty much all of the helmets of that style that I've seen all have snaps along the top brim for attaching a snap on visor. If you can't find a helmet without the snaps then you'll have to just get a helmet with the snaps, remove them, fill in the holes from where the snaps were and repaint it. That is unless you plan on making your own helmet from scratch but I think that buying a motorcycle helmet would be easier.
The visor might be a problem depending on what it looks like. I know that the visors on the Unicorn helmets are impossible to find now a days so the Science Patrol helmet visors might be impossible too, hard to say without a better look. But you may be able to find an existing visor that either matches or is close since it doesn't look too bubbled which is not that uncommon now a days.
I did get the communication pins, but still looking for a SuperGun. I haven't made molds before, so I'm not sure if I could make the gun myself. :confused I was planning on giving a go at making the ear greeblies for the helmet. Oh, I am starting another prodject to go with the outfits.:love
