RE: Old futaba radios
If it were me I would put them up on a shelf and admire the history of how far our equipment has truly come. I suspect your transmitters cost as much new as many present day multi channel computer
transmitters?
You have sever issues with those old radios. New Battery's required and were they "narrow-banded", etc.?
I see such as you have at swap meets and mostly there are no takers.