Bake time for smaller pies?

It will be quicker, but it's hard to say by how much -- just keep an eye on it and follow the visual cues. If the crust is browning too quickly or the edges of the custard are cracking before the rest is set, cover the edges with foil and turn the temperature down a bit. When "only an inch circle in the center of the filling remains liquid" it's ready to come out!