I'm hoping to connect my Model 19 Teletype to a radio transceiver for use with RTTY. I've learned that I need a terminal unit to do this, but haven't found a ton of information about what terminal units to look for. 

What can I look for to find a terminal unit? What can I search for? Is ebay my best bet for finding this sort of equipment? 

Thank you for the help. 

73, 

Aidan W9POG