Amazon.com: OLED Display Module for Mechanical Keyboards & Arduino, 3.3V-5V 0.91 Inch SSD1306 I2C (Black) : Electronics
4 Keys Rgb Mechanical Keyboard Keypad Module Rainbow Led Max-key X4 Sk6812 Rgb Full Color Led Button For Arduino Building Blocks - Automation Modules - AliExpress
40% Keyboard Build Is 100% Open Source | Hackaday
ArtStation - Artist hotkey mechanical keyboard (Arduino)
Arduino powered 5-key keypad includes a rotary encoder - CNX Software