Electronics:
x6 30mm arcade buttons
x2 24mm arcade buttons
x1 Sanwa style joystick
x1 Joystick USB board with it's USB cable
You can find kits that include all of these parts on Amazon.
Screws:
x6 #8 Flathead 1" wood screws for holding the bottom plate
x4 small circuit board screws to hold the board
x4 M4 bolts and nuts to secure the joystick.
The author hasn't provided the model origin yet.