I also like this track and had the single. Like you I was surprised that it doesn't appear on CD. From what I can make out, this track was written by Mike Batt (or maybe co written with Steve, I'm not sure) but for whatever reason, Steve doesn't seem to consider it a "Steve Harley track" and seems to have distanced himself from it. I don't know the exact politics behind it but I have collected all Steve's material for years, and have never seen it see the light of day since the first single release, and to be honest, I don't expect to see it again. Hold on to the 45 is my advise and invest in a vintage record player.