The old PK162-308 step motor is obsolete and unavailable from Parker. Replacement options are limited to smaller framed TS42 frame motors, though they are of a higher torque design and may solve the application, the mechanical mounting will need to be modified for the smaller frame size.
The ZETA12 or ZETA6112 drives are options for replacing the PK130 (or PKH130) drives often sold with teh PK162-308 motors years ago. Though their current output is slightly less, their advanced anti-resonance technology can provide more usable torque and may actually perform better in the system.
glh 10/3/12