The composer who wrote the soundtracks to a number of Rare's '90s games is selling the official tracks on his personal website.
Grant Kirkhope has published the official scores to Perfect Dark, Banjo Kazooie and Banjo-Tooie on his personal website. Users can pay any sum they want for each individual track with no minimum fee restrictions.
Kirkhope started work at Rare in 1995, and went on to write audio for a string of the studio's games including Donkey Kong, Grabbed by the Ghoulies and Viva Pinata.
You can look through his audio catalogue here.
Further reading: LIKE: The music of Rare's David Wise