I'd say that $150 is a good price for almost any pin that is not completely gutted...
I have the same machine. Gottlieb Road Race circa 1969. I got this machine when I was 2 years old and it has been sitting in my grandfathers garage for the past 31 years. I am planning on moving my Road Race to my house within the next couple weeks and plan on doing a full restore.
My cabinet is all original, but the paint has slowly cracked and the legs are quite rusted. The power cord is almost down to bare wire and some burned out light bulbs, but other than that my pin is playable. I too am wondering how difficult it is to work on EM machines... this will be the first ever machine that I have done anything to. I know that I need to replace all rubbers, light bulbs, and the right flipper has always made a grinding sound (but works) ever since I got it. I am probably going to try to find replacement flippers and the flipper mechanics. Not sure where to even start looking for these parts at...