Yeah, Omnia Opera did the same thing too. Crazy dayglo psychedelics for covers. Think those Ozrics tapes have been released on CD since, 'Sliding and Gliding' is still one of my fav' Ozrics tracks.
I've got a 2cd Comp called "Afterswish" which is made up of a load of the cassette stuff. Not sure how complete it is, but there's a fair amount on it.