[kevingross]

I'd seal the paint with Wurth Metal Prep, which will put a phosphorous layer on the bare metal, then Wurth Rust Guard, a great primer, or something like it. Follow with the Wurth Stone Guard, maybe apply it with a small brush like a solder brush, you can get good texture and lap to the existing pebble texture nicely. Paint over the stone guard.

When doing spot repairs like this, the product you use is less important than the care and technique you apply. There are lots of great products out there, I happen to use Wurth.

I hate body work with a passion, just slightly less than I hate corrosion, so ymmv. Good luck!