Made by Lundell
I think from Cherokee, Iowa.

I don't think they are made anymore either but can be seen for sale from time to time.

Good picture of a set installed in this thread.

https://talk.newagtalk.com/forums/thread-view.asp?tid=546839

Robert Greif sent me an email telling this info. when I inquired before. He probably knows the most about them as he has a set and has done searching to find more of them. Also sent me some pics of how they mounted.