Slide stop spring is blued, so I'm leaning towards an original finish. Took it to the range yesterday and it really runs great. There are a couple of spots on the grip where the finish is thin and shows some light rust. I've oiled the exterior twice with a light gun oil, and it is just soaking it up. Any suggestions about how to keep up the finish and fight off the rust?
Just maintain a light coat of oil after each shooting/cleaning. It doesn't have to be swimming in oil and it will not continue to rust. What you see happened probably over decades not days or weeks. Guns that are maintained and kept in a stable environment are not going to rust at any accelerated rate. Take care of it and it will likely look no worse than it does now in 20 years other than normal finish wear.
