Thanks for the appreciation Maurice and Arnold.
You are right about the reblueing. When I restored the machine (it's been a while), I didn't think about it. I was also still looking for a suitable means to bronze non-ferrous metal at the time. In the meantime I have found what I was looking for. "Nerofor" from Ballistol. I am very satisfied with the agent. I'm still waiting for the original chimney. Maybe I disassemble the machine again and then reblue the boiler. Although, I was really glad that all connections to the boiler were tight after assembly.
Have a good day and stay healthy.