I guess you missunderstand something here. That killerfish dont provide the source audio files should be clear due to licening. The dev stated you can put an access your files where ever you want in your override folder. If you go through the config files you can clearly see the filenames. Take a look at the modding guide. In my test sanbox mod i changed the menu music for ex if you want take a look:
http://subsim.com/radioroom/showthread.php?t=231750