The gear is marked 4-910-402-01 Gear (2) Loading or 4-910-454-01.
Sony CDP-70 loading gear 
Sony CDP-70 loading gear
Faulty gear can be replaced with 3D printed one. Replacement gear was fully tested for correct operation.
Gear position in the schematic:
Gear is compatible with CDP-30, CDP-70 Sony CD Player.
However, it might work also with other devices – just check your service manual.
Available for purchase in e-shop.