Well, for a small band a regular site should be enough, just crypting it behind a password. Myself, I would also make the music into modules and sell them as separate packages (+ each password automatically invalidate after a day or two).
You will still need to know some coding, or find a program that does the crypting for you. IIRC, there are a few for sure... Anyway, it comes pretty much down to finding your own company, and making it sell. I highly doubt that anyone of the existing ones will do it for you -unless you are the next "U2" or "No Doubt."