Do I need hardware to bolt this in?

Fasteners aren't included with this bracket. You'll need factory bolts or Grade 8 replacements — pull your old bracket and reuse what came out, or grab hardware at any fastener shop.

Will this work with an aftermarket bumper cover?

This bracket is engineered for OEM-profile bumper covers. If you're running an aftermarket cover with a different mounting geometry, test-fit before final installation.

Does this come primed or ready to paint?

It ships as a raw panel. If your bumper cover is painted, you can prime and paint this bracket to match, or leave it as-is if it's going under the cover where it won't be visible.