I've listed a Symek TNC31S modem/TNC setup for 38,400 bps FSK downlink and 9,600 bps FSK uplink on Ebay, Item #330220133088.

This unit is for high speed downlink satellite use as when AO-51 is in 38,400 bps downlink mode. These units are still in production and thanks to the devalued dollar currently sell for about $420.00 new. This one is in perfect shape. Manuals can be found at www.symek.com.

Thanks for looking.

-Stacey