Not too familiar with the older outboards, but that doesn't look "natural". Is this your motor or one that you are considering buying? If it is the latter, why is the person selling it? Does it run/have good compression?
Upper motor mounts are bad.You have to pull power head to fix.New ones cost about $50 a piece or you can fix with a rubber plug.I have fixed quite a few with rubber plugs.
Don't even know if you are still paying attention to this thread or not. Just did a 15 this week. Pulled the powerhead. there are three pan to powerhead mounts that are apparently missing or loose or at least some are missing or loose on your engine. Underneath, at the front of the pan is a piece of square weather strip captured between the bottom of the pan and steering bracket. It is about ten inches long and has a 90 degree bend in it. Yours looks like it is missing that as well.