This is the last trial piece listed in the Judd book. It is unlisted in Pollock. It is described as a standing eagle struck in tin which has been copper plated.
If it was for a fifty dollar pattern, as opposed to an eagle for some medal or other, then it was struck in 1877. To my knowledge, it is not known if this is even a mint product.
Whatever it is, the piece is unique and is ex 58 ANA lot 2051, Terrell-Bowers and Ruddy 5/73, Bowers and Merena 1/01, Heritage 1/04
Photo courtesy of Heritage.