That motor looks like it lost a battle with chain!
Retrieving your tackle box can be a problem. A diver would be useful but I've caught all sorts of things with my blade baits, Best one this year was a pair of Orange camo pants and a week later a buddy caught the matching jacket. As bad as they smelled, the owner may have been in them when they sunk!
You might get lucky with a snagging hook but without a diver I think it will be just luck!
I have a 3# coffee can full of lures we have retrieved as well as a dozen or so anchors, anchor ropes (Always good for some lures) and every spring we make a special trip with a grapple to pull up a steel cable ~1/4 mile long to salvage a lot of misc lures never fails to amaze me is how some people manage to snag a floating bait on a cable in 25FOW. Lost so many lures on the cable, went out on a buddies big houseboat and messed around trying to figure out what the snag was. We cannot get it out but there is enough slack that we can get it up and salvage a lot of useless relics.
Good luck and hope the motor is not as bad as it looks.