Main seal isn't leaking, leave it alone, Looks like the sump gasket is leaking, one of those bolts is wrong or not tight, try and get a few that match the originals, and tighten them up properly.

The original pilot seals last to infinity if you look after it, pull off the clip and cover, degrease them and the bearing, provided it turns smoothly, pack it with fresh grease, put the cover and clip back on. This is no different to front wheel bearings, they should last a million miles, provided you service them regularily.