Why does it look like they pad is hitting the hat? The “Rust ring” will go away if you really start to use the brakes. Normal street use will not eliminate that ring.
The hat is most likely aluminum. Depending on what the pad material is, it’s likely to wear the softer aluminum hat and area around the fasteners as you use them based on the image. That would be a definite NO GO for me, and likely a failure hazard over time.
