The top part looks like it could be something like a vegetable peeler, but there's not a place for a blade. The handle on the right side does pull out for you to unlatch and spin it 360.
As wild as it might sound, I would email these folks, the American Picker people. Since they've seen so many weird and crazy things in their day, they might have an idea or know someone that would. Please keep us informed as to what that is.
On the main handle near the metal part is the number 11. The metal part could have been painted black before the rust. Another guess has been a detachable handle. The side handle/lever turns and the cross piece grabs and locks onto the cooking utensil???