I did take down the fixture and look, but the only marking I saw was a very faint "RV LUMINAIRE VR 30520" and a search did not bring up anything specific.
This is the closest thing I found based on the photo and dimensions:
The bulb looks different, but it says "921" which is the same bulb type my existing fixture uses.
I think I will order one and give it a try. Just trying to find something that fits the same mounting holes, etc. if possible.