With the halves of the stick removed, the circuit boards are exposed.

(3) 6x6x4.3mm momentary switches for buttons #2, 3, 4. Omron B3F-1002 or equivalent.

(4) 6x6x4.5mm right angle momentary switches for the Hat buttons #9, 10, 11, 12. Omron B3F-3122 or equivalent.

(1) x 6x6x7.3mm switch for Trigger button #1. Omron B3M-6009 or equivalent.