Strange Supercharger Question

[Ubiquity]

I recently bought an 08 215 speedster that runs fine. Female adult owner who really had no clue as to maintenance history other than her seadoo dealer serviced each spring and fall. 55 hrs showing and from condition of boat I'd say legit. To be on the safe side on an uncertain history and a seven year old boat, I was going to have the supercharger rebuilt. Pulled it a few minutes ago and have questions. One side has 2014-2 cast in and the other 2015-2. Appears metal washers. I know appearance is no guide, but this supercharger looks brand new. Are these supercharger casting dates??? Also there is no visible oil hole on the mounting stem and the bearing is visible behind the inboard washer. Can anyone give me some more insight?