Yes. It was common for operators to "update" the look of older bingos with cheap metal rails over the wood rails after metal rails became standard from the factory on new games.
Sometimes they would take off the wood rails and chuck them, so you are lucky in that regard.

Not sure about the bottom.

The bottom nail holes might be from an aftermarket metal pan that covers the entire bottom of the game and wraps up both sides of the cabinet a few inches. Wico used to sell them.
Quite a few of the bingos I have seen over the years have had large break in holes under the cash box.

AKA "ghetto plate"

http://www.zolatone.com/

This is the paint Bally used to use. Mostly the gray speckled as seen on Bally Spinner games and others. I saw an article in a mid-50's Billboard magazine stating that Bally had started using Zolatone paint on their games. Good for hiding imperfections.