Kirk here reporting a good experience at Toyomizu no yu, a “kazokuyu” (private bathing) facility in Shisui-machi. Unless you happen to live in the area you’ll need to drive there but my wife and I were glad we did. (We bathed in the “hinoki” bath that I think is first picture. There’s another type of private bath outside.)

https://www.toyomizunoyu.com/