The Internet Archive has a usenet collection [0], and whilst I didn't see rec.music there, I did see usenet-music [1]. The archive seems to use mbox for everyt

The Internet Archive has a usenet collection [0], and whilst I didn't see rec.music there, I did see usenet-music [1]. The archive seems to use mbox for everything, so you'll probably need an email client to read it, but that's it. [0] https://archive.org/details/usenet https://archive.org/details/usenet [1] https://archive.org/details/usenet-music https://archive.org/details/usenet-music