It's a streatch, but MAYBE at a resteraunt supply store, if not they will have a no-rinse sanitizer of some sort there....I think Chuck Talley mentioned that originally starsan was meant for the resteraunt/bar industry as well as the brewing...or was that iodophor...
In a pinch I'd use hydrogen peroxide. Same effectiveness as bleach for sterilizing, but has the benefit of creating water as a byproduct. It uses oxygen the way bleach uses chlorine. You'd need a couple bottles, but its cheap.