I remember reading somewhere that there were several Disco versions of the Star Wars theme in the late 70s, but the only one the internet seems to acknowledge is the Meco version. Admittedly, that's the version that I seem to remember as well, but this video clip presents another that may or may not have been in wide release:
http://www.youtube.com/watch?v=ZwMQt9LUP5I
Do you know of any other Disco versions (from the Star Wars era, 1977-1983)? I'd be interested in tracking them down.