Model # m460-g 131719100 013-96291 0123a7 131918200n are the numbers on my timer. Need timeer, part that the knob is on is all stripped, can that shaft be purchased separately? Or Do I need the PS416776 or PS418620? Or something else all together? Not sure what the machine model # is but it is a stackable Gibson Heavy Duty Automatic Dryer Interior Drum Light Gibson. Thanks