If you have a remote starter switch, you might try loosening an injector line at the pump and cranking the engine -- you should get fuel at the loose fitting, but make sure you're safe if the engine starts.
Lift pump parts aren't available any more but complete pumps are, from American Diesel, 804-435-3107, or Fred Warner in Marysville, WA, sells on Ebay.
Injectors aren't very user-friendly and you need a pop-tester to set them up after disassembly, but a local diesel shop could probably service them for you. American Diesel and Bomac Marine, 954-766-2625, both have exchange units.
Additional bleeding would be my first guess. If the fuel drained back from the line while changing fliters the squeeze bulb will be your best help. Get fuel coming out the bleeder ports on the injector pump, put the plugs back in, and crank the engine with half throttle.
It is possible to fill a lift muffler with water by cranking a lot. If you have one installed you might want to drain it if it has a plug or remove an exhaust hose to check.