The Universal Indicator series is rather mysterious in origin. It's generally held that Richard D. James worked on the Red album with Mike Dred, and some believe that RDJ worked on Green. One can only guess.
Here are the Blue and Yellow EPs in 128k MP3, and Green, which was pressed into 3--12"+10"+7"--discs, in higher-quality VBR MP3 format; don't remember exactly where I found these recordings. Note that my UI: Red upload is a high-quality vinyl rip in FLAC.