You can use a Sega Mega Drive controller. See previous posts.
Have you tried the CD32 Competition Pro Joypad?
You can connect an A4000 keyboard to the AUX port on the CD32 (You can also connect a modem or serial link cable there). I imagine you could get an in-line converter from PC to Amiga keyboard interface, but i`d advise a second hand A4000 keyboard. A keyboard for the A4000T will not work without an adaptor.
