Mamiya C's TLR series are nice, but heavy. If you are into 6x9, you can try the Horseman "tech" camera, like Horseman 970. They go pretty cheap and lens are pretty good. They also have some tech movement on both the front standard and the back one.
I've one of those with 3 lens, and they are pretty fun to use, although they are heavy and slow.
I would say your budget could get you one camera, back and probably 2 lens.