New Britain Precision Set Screw Cylinder Clamp Assembly - 2 Studs (excellent) 

These are used.  Excellent Condition.
Measurements of the Stud -   Diameter .990 in / 25.2 mm   ;  1.48 in diameter of head  / Right at 7 inches OAL.  
Will ship international.  

please ask questions.  Please look at pictures.