...from Ed at DiFatta. A tad pricey ($40+)

given what you get but SamW is right that something is missing.
This is the portion of the shaft inserted into the flywheel and the assembly helps center the driveshaft. To be precise, chances are the bushing itself might still be embedded in the flywheel! (Along with the spring and snap-in locking washer) Make sure these are not still in the flywheel before reassembly or you will not be able to reinstall the shaft!!
The concave bit on the end actually pivots within the cylindrical bushing compensating for engine movement in relation to the driveshaft. The assembly needs to be well lubed as after some time the pressure of the spring could force the pivot tip to ware through the bushing.
Tip: You don’t need a press to install but heat the new tip and coat with oil before assembly. Getting the snap ring in can be fun.
Good luck.