In a pet store? Normal BP's. Why? Because people who frequent pet stores generally want $40 snakes. Normals are $40 snakes. Morphs are not.
If this is a specialty reptile store, then that's different. But if we're talking puppies/kittens/fish/birds/mice/few reptiles/run of the mill kind of pet store, then frankly I wouldn't stock morphs at all. I would, however, make contacts with reputable breeders to special order morphs for customers if they come in and ask.