Wow! And that bearing is really a PITA to replace. If you have a boat yard nearby personally, I might as well just find a LU to replace it. Where are the roller bearings? Pretty sure they all fell into the clutch and pinion gear assembly which locked the entire unit!
One of the best boating practice is to always check the condition of the LU gear oil at the start of the season. You do not have to drain it all the way. Instead, just keep it in a vertical position and drain only about a spoonful to check clarity. Since water is heavier and stays at the bottom, you should easily see if water is present because it will drain first.
If water is emulsified in the gear oil, then clarity will be really bad, like colored whitish, milky or very light brown. Do not confused brown-dark brown as bad oil especially if you just got done running the LU. With air mixing with the gear oil sometimes it turns into dark brown instead of clear due to air emulsification. There's nothing wrong in this case except you need to top off the gear oil.
Depending how often you go out on the water, I personally check gear oil once a month and I go out about 3~4 times a week.
