When first got Westy, I think Airstream replaced water pump twice under warranty.
Then, pump died but was out of warranty--I purchased two from GoWesty which looked identical to the Airstream ones but marking said Leisure Products Cerritos Ca.
So many years have gone by and the GoWesty one has lasted much longer than Airstream ones. Today, it died so I just installed the spare.
Looking at the GoWesty website to order some more, see the markings are different--Made in Germany.
Tip: Sometimes, the water pump may become disconnected from the outlet tube. Some folks have added a clamp. As it's hard enough to replace in tight space, I just keep the white electrical wire cord short and straight as held by the rubber grommet--so it keeps the pump relatively vertical against the fresh water tank back wall with not that much room to move. Makes more difficult to become dislodged.