How does that Amex replacement work? How long?
Anyway you have a couple of options. I've done something similar to some wheels I had. I called Easton and bought a new rim to replace the front because the bead surface was dinged up ($60, so cheap!), but the back braking surface was gouged similar to what you have and I just rode through it. They're fine now. your brake pads will smooth out the rough spots over time, and you will likely go through pads faster than you would otherwise. As long as the damage isn't structural (and not the front) I'd use it. That's me though.