CPI MCR220 Tone Remote and Termination Box?

First post, brand new so please bear with me. I was recently given a CPI MCR220 tone remote and my intent is to use it with a VHF GM300. My understanding is this remote needs an MCP200 termination panel to interface with the radio, although it didn't come with one. I'd like to know more about the background and vintage of this equipment, the basic elements of it's operation, etc. And, if anyone has any further insight or sourcing for a termination panel, that would be as greatly appreciated.



Thanks for your time!

-ZM

CPI MCR220 Tone Remote and Termination Box?