It was one of my first as well. I always thought the fight between Unico and the baron was really exciting! (And got annoyed when other cartoons didn't do that.) I have never seen a subtitled version though.
Unfortunatly I don't remember where I saw the manga. It was just a website probably from around 1997. It wasn't a complete collection/scanlation of the manga so much as a couple of scans talking about it. I remember something about translating Unico as female instead of male but that is it. Sorry I couldn't be more help.