What you have there is a 19 station rotary/tone intercom unit. I guess the basic questions are:

1. Are telephone sets connected to this unit?
2. Are they all either rotary or tone or a mix?
3. What is the intercom used for? (Stage hands, director, cast?)
4. There are other units that work exactly as the Melco, however they would require some rewiring. Are you capable of installing a different unit?

I have worked non-profit for years and as Dave wrote, if they want/need it badly enough, they can find money somewhere. Professionally speaking, a wireless solution would be much more versatile and available.

Rcaman

Americom, Inc.
Where The Art And Science Of Communications Meet