Uploaded all the beta 1.8.1 versions I could find in my old DropBox folder to https://uristqwerty.ca/mods/craftguide/. Any other versions worth adding soon, rather than in the distant-possibly-never future?
No clue if the files still work, I don't really feel like putting together an ancient Minecraft instance to test, so I'm assuming that no bits have flipped in the past... 8!? years. Hope it work out!