I have had plenty trouble with that elbow but if it’s ss now then I would expect that to last for years. I replaced the 1.5” exhaust hose between elbow and water lift
with a corrugated silicone one so that it’s easy to take off the elbow.
Other spares I can recommend: a couple of V-belts. I recommend to go to O’Reilly’s or Napa to get a Gates belt which is better.
Next is the raw water pump
. Buy a complete one from NL, including the gear
. Then buy the rebuild
kit. I got a no-name kit from eBay for $85. I saw a rebuilt pump
there as well.
Next is a couple of the relays used (standard automotive 30A)