I just got one of those from Powell's City of Books in Portland for $13.50 in great condition. The $15/with shipping offer is a steal. Anyone who appreciates climbing history and culture should have one of these.
Others in my collection that I'd put in the same cherished category: Clarence King's "Mountaineering in the Sierra Nevada" and a very special slim volume "An Ascent of Half Dome in 1884" by Alexander Phimister Proctor (Hermes, 1979 collectors reproduction).
For modern books that are "instant classics" (an oxymoron), I cast my vote for "Exploring the Highest Sierra" by James G. Moore. The definitive story of the California Geological Survey and its exploits.
Roper's "Climber's Guide to Yosemite Valley" and the Sierra Club totebook "Starr's Guide" would also be early-edition collectibles, no? (The ethics references on where and when to apply a hammer and pins to an intractible problem are very rich. Suitable for dramatic reading at a climber's dinner party. When was the last time you were given beta that included: "Bring at least 25 iron pitons of various sizes ...")