Hey SD,
So you feel the grit when you open the bale and spin the spool with your finger? If not, I wouldn't think it's the sealed spool bearing. I was thinking you were feeling the grit when retrieving the line. If that's the case I would look at bearing and races on the roller clutch bearing (parts # BNT 4224, BNT 4225, BNT4313.) This is just a suggestion from an ignorant fool looking at a reel schematic.