In short, I've been looking for this soundtrack for several years (since I was about eight :D) and I can't find it anywhere.

The game was for the NES, was produced by Hudson Soft and was released in 1991 in the US.

The main site has it in NSF: http://gh.ffshrine.org/egm/4/671

Yaaaay! I had no idea. Thank you very much. :)