My step father has retired from the machinest trade as well. I built him a shop and he is building bull dozer and track hoe pins . Some cost between 4 to 6,000 for the pins. My step father is taking the worn out pins and turning them down to a uniform shape and then sleeving them with strengthened steel sleeves. Not really what you are looking at but has less ''RED TAPE'' and liability so to speak. He ran a monarch and wrote the programs for his company . It was a million dollar machine when they purchased it . The tooling was from 600 to 2000 dollars. I can only imagine how much your tooling cost. What kind of machine did you operate?