llegoff's SCART adapter for the Pi400. Plugs straight into the back GPIO pins and includes left/right audio pin mappings too since the Pi400 has no 3.5mm out. : r/crtgaming
MiSTer VGA to RGB SCART Cable – Ultimate Mister FPGA
Raspberry Pi 40 Pin GPIO Cable Extension Wire for Raspberry Pi 4B/3B GPIO Board - AliExpress