As someone here once said any grease is better than no grease.Lbriplate 105 would work.
If I was doing it I would use any lube including ep 90 and check it anually.
Any marine grease, or I use gray anti-seize. All DIY will have it somewhere in there garage. And yes, your prop should be taken off, and clean splines, inspected, and re-lubed every season.