I have been able to purchase lots of old Agfa Billy Record 6x9 folders with the Anistigmat 105/8.8, 105/7.7 and 105/6.3 for under $40 USD, including shipping. The older Agfa folders have leather bellows and I have yet to find a leaky one. The shutters are usually pretty simple and even if they are a bit sticky when they arrive they seem to respond well to having a bit of exercise. (I'm going to have to remember the exercise trick when I get as old as they are. )
The lenses provide a pretty good picture if you work within their limits and always use a hood. I just make mine out of cardboard painted flat black on the inside. Though they have a small aperture even wide open it can be quite surprising how many pictures are possible outdoors with the small aperture and shutter range.