The Wurlitzer Kit 219B Remote Volume Control is designed to be used in models
3700, 3710, 3760, 3800, 3810, 3860 and 7500A.
These models use stereo amplifier type 556. 
It can also be used with the earlier 551 and 553 amplifiers found in the 3500 and 3600 series.

This listing is for the motor assembly and other parts seen in the photos. 
It is clean and in good condition but I have no way to test the motor.

You are welcome to copy and save the Installation Instruction scans shown on this listing.