Welcome aboard! You got a good deal at $50. The decals are in really good shape on that one. Wipe off the WD-40 and oil everything that looks like it should move with sewing machine oil, including everything behind the cover on it's nose. WD-40 has it's uses but isn't a great long term lubricant and can dry up and gum up the works on your machine eventually.
While you can sew some heavier materials with that machine, it was produced for home use and really wasn't built to take a steady diet of leather and canvas. If you like mechanical things you'll find it's very easy to get hooked on old sewing machines.
Rodney