I'd probably just clean all that nesting out of there and check the compression before pulling it off the boat. If its got good compression, a new leaver can usually be found on fleabay, there's a plastic bushing in there and usually a nut holding the catch on the inside. Soak it with penetrating oil, work it loose and remove it, clean up the corrosion in the hole and reassemble. Broken levers are pretty common. Most have a small oil hole above the bushing that lets you add a bit of oil every so often.
The 35hp motors are good motors, they're a good combo for a light boat.
My 35hp does better on my aluminum boat than a heavier 50hp did mainly because of it being so much lighter on the stern.