I sent requests to both Colaw and Arizona RV Salvage. Colaw said they didn't have the part. Arizona RV never responded back.
I found what I needed on eBay for $115.46 (including tax). The seller is www.trucklinerparts.com
out of Decatur, IN and it looks like they sell new but slightly damaged units that were intended to be installed in motor homes/trucks. I ordered on 9/26 and received it yesterday, 9/30. The damage on the one I got was just a broken tab that was intended to secure the primary incoming 12V power cable, likely to prevent it from working loose under road vibrations. A few cable ties can easily remedy that defect. Shipping was FAST, so I highly recommend the place. The module is now installed and works fine! Needless to say I'm happy to have saved $800+!
Thanks for the recommendations!