Yeah, unless you do something along those lines or just stick to writing audio CDs or stealing music like everyone else, you're fucked. Your headunit doesn't have any DRM, so it's locked out of playing the music.
edit: Ever heard of ? It has ridiculously cheap prices and gives you good ol' MP3s. It's technically legal in Russia through a loophole, and appears to kinda be legal over here in the US but it's a grey area. That ambiguity, though, is good enough for me. I use it when I can't find a good copy of something I'm trying to find.
