For sale is a used military surplus flywheel. I have reasons to believe that it belongs to Onan DJC engines, perhaps to water cooled J series diesels, doubtfully air cooled. You decide. Numbers on the side are 30554-88-20234 MFR-44940.
While it is somewhat rusty, it has no damage like missing teeth etc.
High shipping cost is due to its weight, almost 60 lbs.