I think this is the store in Lone Pine that Chicagowright refers to:
Elevation Sierra Adventure Essentials Inc.
150 S. Main St.
(Corner of Hwy 395 & Whitney Portal)
Lone Pine, CA
Phone
760-876-4560
http://www.sierraelevation.com/
Also, I keep a few carbide ice screws with me. These can be added to the bottoms of boots. (This assumes that the boot treads are thick enough for the screws).