Good sources for Injection Pump/Injectors

I'm looking into replacing the pump and injectors on my '83 K2500, which is basically bone stock except the previous owner replaced the pump sometime in the past with a used unit with unknown mileage. We have an injector shop here in town, but it was recently bought out and I haven't heard good things since. Does anyone know of any good Stanadyne shops in the Central/Northern California area? I'm willing to order the parts from out of state too from a good shop. Has anyone used US Diesel Parts (Gomer's) or Oregon Fuel Injection? I see that US Diesel Parts uses a steel sleeve in the advance bore of their rebuilds to help with the wear.

Also, in regard to injectors, some say to just go with new Delphi units. I see that US Diesel Parts has new OEM Bosch units and other shops rebuild them. Any thoughts on the Delphi/Bosch/rebuild comparison?

Thanks a lot.

Hi Bob
I have bought a number of Mil Spec pumps off of eBay really cheap.
The Mil Spec pumps have ceramic parts inside,which make them tougher than civilian pumps. The Mil Spec ones will run on jet fuel without damage.
As to injectors i did the same and bought new Bosch from eBay as well,but i bought before i needed them.

Thanks a lot for the info. I’ll check that out.