The Carl Zeiss Planar 1,4/50 with C/Y mount is a typical representative of the 1.4/50 mm

Sample Images

 Specifications

• • Diameter: 62.5mm
  • Length:  41mm
  • Weight: 290g
  • Filter Diameter: 55mm
  • Number of Aperture Blades: 6
  • Elements/Groups: 7/6
  • Close Focusing Distance: 45cm
  • Mount: Zeiss C/Y

More information in Zeiss’ official data sheet.

The Carl Zeiss Planar 1.4/50 usually sells for around $190-260 at ebay.com (affiliate link). 
In Germany you can buy it for 160-230€ at ebay.de (affiliate link). 

The younger MM version usually sells for a little bit more than the older AE version.