Depends how much got damaged. With your initial description the starter pulley needs replacing. With the possibility of the recoil spring and starter clutch but you need to remove the starter clutch and try find out why it tries to stay engaged. As said it could be a dried out oil problem, or it could be binding on the top of the crankshaft. Usually with it trying to stay engaged it will squall a lot with possible pulley and recoil spring damage.
If you remove the starter pulley it need to be re-torqued to 55 ft-lbs. Use a torque wrench and not the hit it with the impact as it can damage the flywheel.
For actual part numbers we would the model, type, and date code to look-up those. These are usually locate on engine tins.
