Hi and welcome Aran!
There was the boxed set
Worlds of Wonder that contained three genre booklets; one of which was a supers genre called
Superworld. This booklet was expanded into the supers RPG boxed set
Superworld.
Worlds of Wonder - Wikipedia, the free encyclopedia
Superworld - Wikipedia, the free encyclopedia
You can find used copies of these out of print games on eBay, Amazon, and similiar websites. RPG.net has a large and active RPG auction/trade community as well.