A body sealed axle bearing

Your car was probably converted to "green bearings". It's pretty common, but it's not an OE deal so you probably won't find a cross reference to whatever car it is you've got.

This is likely what you've got in there, or at least a version of it
Mopar Green Bearings for 8 3/4" (8.75) and Dana 60

If you can measure the ID/OD of the bearings it will help, just in case something else has been done regarding the axles/housing. Not likely but stranger things have happened. Cass @DoctorDiff is the expert and should be able to help you figure out what you've got.