Dean:
Replacing the pump at 10000 miles for the type of cars we have and as anal and particular as most of us are would not be considered out of the norm. Given that you have it opened up and it is readily accesable I would really consider it. If the pump you have is the type with the bottom plate supporting the pump shaft, then you have the best type available. Internnally it is quite common to find scoring and grooves on the working surfaces, but this is also what reduces the output and thus reduces pressure. Here is a source for an upgraded version of that very pump. They are up in a suburb of Fresno. Very good to deal with.
http://www.precisionoilpumps.com/ima..._Race_Pump.jpg
http://data.melling.com/TECHtips.php
This is the "heart " of the engine.........a transplant when necessary is not out of the question. It will be the best $75-$100 you spend.
I also noticed that Melling also offers a line of internally Phosphate coated series of pumps that have a 25% increase in volume. These are in their Performance line. Part # 10833
10832
Stock volume gerotor set assembled to an extended drive shaft that allows for additional support in the
cover. Supporting the drive shaft in both the housing and cover eliminates dynamic shaft deflection at
increased RPM levels. The cover is doweled to the pump housing to assure alignment of shaft bores. The
housing and cover are CNC machined and maganese phosphate coated for wear and rust prevention. The
relief valve has a pressure adjustable screw-in plug instead of a cup plug. Works with the original bolt-on
pickup screen assemblies"
10833 The same as 10832 except gear rotor displaces 25% more volume than the 10832.