Ariens 53127700 – Replacement MPN: 03188300 GEAR CASE SHAFT & KEY Genuine Ariens Part # 53127700. Ariens 53127700 03188300 GEAR CASE Shaft & KEY. Ariens Part Number: 53127700 Replaces Previous MPN: 03188300 Compatible with the following Models. We are proud to be a factory authorized retailer. We use several different carriers and choose the most economical for the item and destination based on the estimated transit time displayed. FixMyToys – A Division of Ball Equipment.