The so-called transitional half dollar using the reverse of 1866-1891.
These and the other "with motto" patterns of this date and also 1863 and possibly 1865 are actually restrikes made circa 1869 and into the early 1870s and were offered with restrikes of the other denominations in complete sets.
Examples were struck as follows:
Silver J391/P459 with about a dozen known.
Copper J392/P460 with about a dozen known.
Aluminum J393/P461 with only 2 or 3 known.
Nickel J394/P462 with only 2 known, one ex Woodin-1914 ANS exhibit, Newcomer and the other was part of a nickel set from the trime to the dollar ex Doughty (1891), H.P. Smith (1906), Brand (journal #33867).
Photo courtesy of Superior.