You never specified what year model your motor is. Most motors can be converted but IMO you probably wouldn't want to pay a mechanic/shop to do the conversion on an older motor as the conversion (labor/parts) cost could exceed the retail value of the motor. If you do the conversion yourself and buy used parts from ebay or the like, you might be able to do the conversion yourself and make it worth doing. If you've got a good running short shaft, you might be better off to sell it and buy a good used long shaft of equal value.