The Steering Wheel Optical Encoder of 60 Slot for G25 / G27 Old Version Driving Force GT Steering Wheels Systems Spare|Replacement Parts & Accessories| - AliExpress
BRASS OPTICAL ENCODER BY CM LASER SERVICE - www.cmlaserservice.com/index.html
Just for reference) Logitech G920 Wheel falling out of calibration / becoming off center during gameplay : r/simracing