I know what we need.
A normal 104 key keyboard.
And on the top right, a big wheel that you use to turn a big drum.
Along the top of the keyboard, a long slit through which you see a row of characters printed on the drum.
A pointer you slide along the window with a button on it to select a character.
When you do that, it's as if you typed Alt+(four digit hex number).
Type anything directly, reasonably small keyboard.