The simplest purest C/Y mount bodies are probably the unber-expensive and rare Contax S2 and the ubiquitous, near-free Yashica FX3. The most inexpensive path to a Planar 50mm is probably a Rolleiflex SL35M. I picked up a like-new SL35M with 50mm Planar 1.8 on craigslist for $25. I have a box of those 50mm Planars (I never use 50mm focal length and these lenses seem to come free whenever I buy a body)