There is a 1-month archive of the SB audio feed (and indeed every feed) on this site. You may have to be a premium member to access it, I don't recall if it's available to basic members. Go to the feed page and you may see a link on the left side which says, "Feed Archives."
I've saved some clips from a couple fires in the last few years but nothing very extensive.
The archive is provided by RadioReference. Follow the link I provided above to the feed page and look for the link to the archive. Again, I'm not sure if it is available to all members or only to premium members.