Making Money from Old Music

When I was a kid, my parents played for me lots of Jewish themed songs about mitzvahs and composed of words of prayers written for children. I heard them so often, I can remember every word of these songs very clearly. But I have no idea the names of the bands that made these songs. I have tried singing them to other people in our community, but no one seems to know what these songs are. I’ve concluded they must have been made by obscure bands that sold few records. Considering how old I am now, and that these musicians were adults in my early childhood, I can’t imagine any of them are still alive today, and if they are, they are extremely old. Would it be permitted for me to make money singing these same songs to others when I can’t track down or even identify the original artists?