I have an original Caves of California book #91 of this very rare 1962 William R. Halliday book for sale. Of the 500 copies of this book that were printed 48 years ago, 175 copies were lost in a "flood". A signed copy sold on this site about 5 years ago. Here is the link to that thread.
viewtopic.php?f=16&t=198&p=1959&hilit=+caves+california#p1959
My copy is not signed but it is in excellent condition. I am asking $500 plus postage and insurance. I can send scans for serious inquires.