I know the image makes me look like a failure as a boater - maybe I can learn to take better photos?
I am going with the theory that I did not damage the drive train but this prop is scrap aluminium now. I'm cleaning up a spare and we intend to relaunch early tomorrow morning (barely got on the trailer at about 10:00 hours and tide falling fast).
Then we need to run the new combination and see if the spare prop is close to performing like the old one did. I doubt it will do any better if I grind in on rocks at cruising speed, though.
I am not sure if the part of the skeg broken off is essential - likely it's main purpose is to protect the prop in a less violent collision.