Drive the old seals out from the inside using a flat punch. You can use the same oil as you use in the engine or the hyd oil you use in your implements.
The seal for the mag/dist end is AA5616R which has been replaced by AH21815. You can also use CR 13569, National 7472258, or NAPA 13569.
The seal for the governor end is AA5613R. You can also use National 480567 or NAPA 8648. The original double lip seal is no longer available so you have to use two of the replacement seals. In stall the first seal with the garter spring facing the pump gears. Install the second seal with the garter spring facing the outside of the pump. Put a small amount of grease between the two seals. The first seal keeps oil in the pump and the second seal keeps the pump from sucking in air. This is what the original double lip seal did.
If the seals on the small end of the shaft cut a groove in the shaft you can install a #99138 Speedy Sleeve to get a smooth sealing surface.
Never turn the pump on with the engine running. With the engine off turn the pump on and crank the engine over a few turns then start the engine.