Looks OK to me. Since that is the outside part that the seal sits in, no place for oil to leak out. Any farther down would be a problem but this can be fixed. You could take the whole thing off and have it heli-arc welded. But I would use a very good epoxy like Marine Tex to glue it back in place with a decent amount on the outside for support. Then when you put the seal in, use some good sealer especially at that spot.