This is crazy! I searched for Fero through Ai a couple of weeks ago and this old thread came up, but before your post. I'm still working on my compressor and did another search today and bang you just posted this, amazing.
I have the same outfit that belonged to my best friends dad. He had it in his personal shop for 50+ years. It was in pretty much original condition although he did replace the motor in about 1970. He has done various repairs (some were questionable but functional) and I did run it about 5 years ago and it would reach 125psi. There were lots of air leaks, so not very efficient. I had planned to use it as my primary air source, but with all the leakage I just rolled it in the corner.
I'm now working on getting back in service trying to fix all the issues. It's a cool old machine. There are no unit specific parts, but stuff from back then is fairly fixable. Hopefully.
I'd like to think I can get a test run, maybe later this week.