This is really cool. Do they by chance offer a rate limited rsync access to archive everything? Asking in the event my small community gets cut off during an economic collapse. If so I would also set up a public rsync mirror.
I had a similar desire but wasn't able to find anything through Librivox directly. Not everything is up there (at least when I was checking), but I ended up going through archive.org for a number of big collections using the torrent option. I've been seeding some of those torrents now for years and they get very little traffic so I have no problem keeping them up indefinitely.