Saving Old Seagulls

Hi All
Took the boat out today and the prop isn't turning when the engine is running.
I took off the washer and split pin and pulled out the spring thing - it doesn't seem to have a 'hook' on it (like the picture on SOS spares page) so the end on the spring appears to have gouged out a bit of a channel inside the prop
So can I assume that the hook on the spring has broken off somehow and I've been running on friction? Its a forty plus BTW. I did clout a rock with it last time out, which stalled the engine - maybe I damaged it? Is the spring the equivalent of a shear pin? If so I will get a spare as well
Could anyone post a pic of what the spring is supposed to look like so I can get the right thing.

Thanks

Dave

So I thought I'd read the FAQs after asking a newbie question (makes sense right?) turns out I need a new spring as its done its job !

so order to sos in the morning (with a spare)

Thanks