found a close reference you can look at. This is called an "Escrow Seloniod" hope that helps...

I worked for AT&T for 30 years. Those are Ring down transformers for older Payphones. That what the multi-contact switches are for behind the white hookswitch lever. the operator would send a signal from her board to refund money to a customer if there was no answer or a busy signal on the line. This transformer was used to release the coins back to a customer.

References:

I don't believe you will find these in any on line source. But you may find one in a local library under Telephone systems and history...Sorry

Reason:
Another opinion was accepted instead.

found a close reference you can look at. This is called an "Escrow Seloniod" hope that helps...

References:

http://www.hawestv.com/wiltelco/wiltelco2.htm