To the buyer below, as far as I know, the album Step by Step was issued on CD, but only in 1982! There was also a 1981 (yes, 1981) German "triangle" pressing on CD used to demo Philips CD technology. I have Step by Step on CD on the Elektra label.
I have never seen a "West German" CD of Horizon, though I wonder if one was made, many of Warner's early albums were "label internal only" 50 copy or less archival pressings used for international record pressings.
I had forgotten, but there's also a Liberty records CD of "Step by Step" that has a different cover but the same tracks, that was made around 1990. That may be the more reasonably priced album if you are looking for a CD of it!