This is a compilation cassette released by the fine Italian label OLD EUROPA CAFE in 1991. It contains tracks from the three regular DARK STAR cassette releases plus one track from the (at the time unreleased) CD "Headtrip", sort of a "Best Of" thing... It might still be available, but actually I have no idea, so you'll just have to check it out at their beautiful website:
PO Box 116
OLD EUROPA CAFE started out releasing cassettes with electronic/ industrial sounds, but has lately also been releasing CDs with similar material. It is run by Rodolfo Protti.