Atari 65XE USB Keyboard and Atari 65XE USB Keyboard with Joystick ports in my Etsy store, and also a version with a Raspberry Pi integrated.
UPDATE: USB Keyboard Kit
USB Keyboard and USB Joystick Kit
These are also available as a kit with the USB keyboard controller and the dual USB joystick board. The XE version comes with the joystick connectors on ribbon cables, to clear the mounting posts.
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