I visited the Whitney Portal Store on Friday May 21, 2004. The Portal store is right at the trailhead bottom of Whitney trail.
Store Hours: May 9-6, June 8-8, July 7-9, August 7-9, September 8-8, October 9-6
When I visited, I saw they had a stack of bear containers that almost reached the ceiling. Plus, they had boxed ones in another area.