Several years ago a hobby/toy store around here was going out of the "hobby" business, and was cleaning out a carton of old dusty Estes diamond pack motor packs from deep in his storeroom, and I offered the dude a buck each for about 80 packs, so I picked up about 240 motors for about 33 cents each. Mostly A's and B's, including about 30 packs of B14's.
It's always fun when you luck into a mother lode like that.