Have you ever heard of or seen an adapter to put a Zeiss or Schneider lens on a Pentax 67? Is there a 6x7 camera that uses Zeiss or Schneider? I suppose a folder or two does but I am not really into folders.
dennis
Zoerk are your people: http://www.zoerk.com/pages/p_pshift.htm
SK Grimes (http://www.skgrimes.com/) shouldn't have too much difficulty if you don't want tilt and shift. You may need the helical extension tube to allow focusing and you will be limited in the usable focal lengths (probably 100mm+).