I like the "old school" approach. You just can't kill those old belt-driven reciprocating diaphragm
pumps. Just have spare belts available.
That said, most of the "fancy" new potable water
pumps are very rebuildable. Mine has lasted three years so far. Before that, I went on line and found a number of places that sold parts
to repair the old one, but it was at the age where I figured a total replacement was worth it.
In the end I also bought a spare pump. Potable water
is something I'd like to have back on-line quickly, and it was cheaper to buy the whole pump than all the possible spare parts
I might need.