Based on this product's specifications, here are some alternatives and similar models
Drive Gearbox for Tryton petrol mower model YYPRKS04 — length 53 mm
Summary description:
Replacement drive gearbox for Tryton petrol lawn mower, model YYPRKS04, with a shaft length of 53 mm. Designed as a mechanical transmission component to transfer engine torque to the cutting mechanism. Suitable for repair and maintenance of compatible Tryton petrol mowers, restoring drive function and ensuring proper blade rotation.