I am sure that you have considered this but it seems to me that your criteria is fairly restrictive.
It seems that you want your student to be able to take street photographs using light, inexpensive, manually operated, cameras with lenses that can be scale focused. Obviously you prefer that they have no meters but, off hand, I can't think of anyone who has manufactured a meterless camera in a very long time, except Leica. And I doubt your budget includes this type of camera.
I was scale focusing on the street many, many years before I finally began moving to rangefinder cameras, but I was using SLRs. You may have better luck finding some inexpensive SLR cameras with 35mm lenses than will finding the equivalent rangefinder style.