My MAP(manifold air pressure sensor) on my 72 1800E will no longer hold a vaccume. I looked inside to see if it was just a seal or something and found that the brass diaphram was cracked wide open half the way around. Now I am having a hard time locating a good used one. New ones are too expensive ($250. from Volvo/$390. from RPR). Does anyone know of a good source for used ones that have been tested or rebuilt? Maybe there is a solid state replacement I don't know about. I found one for $45 at a local yard but I have gotten bad parts from that place before and I am I little leary to do busines with them again. Maybe you have one to sell? Please help.

Thad