It is very difficult to find one of them in good condition these days without losing a small fortune.
By the way, I´m somehow confused about what you really want. In the other thread you sought advice on the 80 CB vs CFE Planar and stated that you want ultimate quality for high res scans, then you opted for the adaption of vintage lenses for awesome bokeh.
If you really want best evenness of resolution from center to edge and freedom from distortion, I can highly recommend the 120mm Macro Planar instead of the 80/2,8. I´ve made some scans from slides shot with both lenses on a Flextight X5 and the 120 Macro is clearly superior. Not that the 80mm is a bad lens, but viewed at full scale, the qualities of the 120mm are easily discernable.
If you want to adapt vintage lenses, I would search for a Rolleiflex SL66. It is very easy to use third party lenses with this camera. Much cheaper than a 203FE though.