This waving design is made to rock your boat. It utilizes a small mini bullet style vibrator. Suggest printing at .2 mm layer height with supports. Due to variations in printers you may want to use some electrical tape to make sure the vibrator is snug in its hole.
base-76.2 mm diameter, 33 mm tall.
shaft-28 mm diameter widest, 147.3 mm tall.
vibrator hole: 18 mm diameter, 35 mm tall.