Futaba Charger and Switch Harness
We're sorryt, but your old Futaba 2GS system would use the old Futaba 'G' connectors. they are the ones with the flat blade-type pins that stick out of the housing at 90 degrees to the cord.
If your transmitter is on 72 or 75 MHz, it would be illegal to use, because it's a wide-band unit. A 27 MHz unit would be OK.
Futaba no longer makes components that would be directly compatible with your unit. By the time you purchased the charger, switch harness, and needed adaptors, you're getting rather close to a similar 2-channel system.
Basic 2-channel systems are as low as $45.00, depending upon the retailer.