Can you get to see the rest of the internals in the pump like in a 722.1?
If so I'd look for more damage before deciding to change the bearing.
If the cog surfaces inside the pump are worn - or it is making swarf(!) - then I'd say don't reuse it. The pump sits on the safe side of the filter remember so anything that comes out of it will end up in parts of the transmission where it can do the most harm.
However, if you think there's nothing wrong with it clean it all up and replace the bearing.
If you post up the size of the bearing I can help find a replacement part if you don't want to go through people such as the dealer or
Ganzeboom - Transmissies - Transmission Parts
(also in Amsterdam as well as next to me on the edge of Germany!)