A couple of points:
A scored shaft can easily be repaired with a "Speedi-Sleeve" (or other brand name) kit. These are very thin sleeves that are slid over the shaft in way of the seal and restore the surface to like new. Commonly used in industrial maintenance
, inexpensive and effective.
The lip seals
are indeed very inexpensive if purchased from a typical bearing supply house. The ones for the Johnson water
pump">raw water pump on our Nanni are around 22 bucks each from Nanni, and 2 dollars each from the bearing shop. Your choice! It is good practice to replace the little coil springs (whether s/s or not) with similarly sized o-rings, thus eliminating one common source of seal failure.
Wear on the cover plate is often an issue as well. On many pumps one can reverse the cover (outside to inside) and double its lifetime, or use the worn item as an excuse to buy a Speed-Seal cover which makes impeller access much easier.
Finally, the bearings can also be sourced from the corner bearing supply shop, and at vastly less cost than from Johnson/Jabsco or your friendly marine
salesman. The bearings may require a press to install, although I've been able to use a bench vise and an appropriately sized socket wrench successfully on mine.
These pumps are pretty simple and well within the scope