Disc brake prop. valve bracket for '71 & later might be something worth looking at. Stamped steel, four holes. If I had to name one single piece that was the most difficult to find this would be it. This is a part needed for disc. conversions with stock set-up on '71 & later cars, possibly earlier ones too. Found one eventually in Texas, used. Forgot all about until I noticed two NOS brackets @ e-bay today. Not sure about demand by others at this time, these were used on all A-body disc cars at the time, I believe.
Hi Frank, Think I checked at the time, none available. They had a repro combination valve, however, I bought one should mine ever fail. Thanks.