Whatever remote transmitter you want (provided you fit a compatible receiver)! The choice is yours.
I'm afraid I have no idea whether the KK board is SBUS compatible or not in which case you may have to wire traditionally from the RX.
The KK multicopter board is a FC only - it cannot connect to a remote transmitter on it's own.
Suggest as Irish sights recommends - go over to a multicopter forum as this is DJI Inspire specific.