In all probability the oil pump will need replacement. There is a plain bearing (like a rod bearing only in one peice) that supports the torque convertor input shaft. Look carefully on the torque convertor for any signs of contact--slight burnishing, copper transfer, etc. That is a dead giveway. Then look carefully at that front bearing--if it does not appear 'as new' with the grey rod bearing look, it is shot. The bearing is available separately, but look very carefully at its race in the oil pump to be sure it has not worked and chewed it out. A very common failure the tranny techs tell me. That bearing is actually a throttling bushing that holds back most of the oil pressure inside the pump, reducing the load on the lip seal around the torque convertor shaft. Excessive clearance lets too much oil leak by, which overpressures the lip seal and you have the leak.