Thank you all for the information! Tackling in order...
The gauge of the wheels is perfect! It sits on Atlas code 148 very well. I was thinking of hand-laid code 125 for my layout.
It seems these models were made from '78-80? Not that it's important, but I'm always curious about the technical aspects of these brass models.
I seem to be missing a few parts. In particular, the eBay posting has 2 rubber air hose extensions that I don't have. Also, there are small bags with that model and a screwdriver I don't have. Is there a way to get a hold of these parts?