No Contax to RZ67 that I know of.
However if you want something similar you could go with the Fuji gx680.
Kapture Group makes a Contax 645 back to Fuji gx680 adapter.
The GX680 is what I would call a Mamiya RZ on steroids.
It's a 6x8 camera but with the added advantage of all the lenses from 50mm to 500mm being tilt shift lenses.
Even a 100 to 200mm zoom tilt shift lens
I had several Mamiya RZ cameras back in the day. They served me well despite the cranky coffee grinder motor drive
You can pick up used Fuji gx680 cameras really quite cheap and the lenses are really good with beautiful bokeh and large format look.
Down side is the size. Significantly bigger than the RZ.
www.kapturegroup.com