In need of stabilizer/puck for a Sony SCD-777ES

Just bought a used SCD 777ES at a very fair price because w/o the disc stabilizer, the seller couldn't verify that it was working properly.  Any words of wisdom as to where I could obtain a stabilizer?  Thanks in advance!
Just wanted to close the loop by saying that I received a puck from dgarretson in the mail today!  As an unexpected bonus, he also included a copy of the service manual for the SCD 777, as well as additional documentation.  Truly above and beyond.  THANK YOU D!!!