Thank you all for your observations from the photos in post #16.
I just came across a 2010 Northern Tool catalog I forgot I had. The photo of one vise in the catalog looked very much like my brother's vise except for the head rotation lock lever. No manufacturer's name was given. The title...
My brother's widow in North Carolina wants to sell the vise in the photos to a friend. She can't find any identification on it. It looks a little like the Yost 750 but she tells me that it has 6" jaws instead of the 5" for the Yost and it's 21" long. I'm sure it weighs lots more than the 63 lb...