Thanks to Otto Skorzeny's great list I've been able to find just about everything I need.
When I contacted "Booster Dewey" in Portland Oregon re: my 57 CDV booster, they referred me to this fellow that rebuilds these units:
Ed Strain
655 44th Street, Unit 2006
Pinellas Park FL
1-888-266-1623
He did a great job with good turnaround (3 wks) and the fees are reasonable. He does have a website, I believe. Very easy to deal with!
I've called both numbers from Ed Strains website and they were disconnected. Ok, I see his business was taken over by White Post restoration in. Virginia.
I talked to Ed Strain a few weeks ago as I was having brake problems with my 1957 Fleetwood and he had rebuilt it a year earlier. He was turning everything over to the new owner at that time
Since the 57 was a one year master cylinder it is important to us that we support the current re-builder.
Thankfully Cadillac saw the problems and did better in 1958!
Thanks for the update. I got my booster back from him this last summer, and did not hear about the change of ownership.