Do you like old lenses? How about trying Voigtlander Nokton 35mm F/1.4? It's not an old lens but you would have the same old lense experience.
Do you like old Leica M lens feeling? Soft as opposed to sharp? Voigtlander Nokton 35mm F/1.4 can satisfy your need in combination with Leica CL or Leica M.
Leica M lens vs Voigtlander lens. What is your choice? Here are some example photos for you with Leica M10 body.