Ill bet that nickel is either dated 1971 or 1972. That design was on the master hub and is normal. In 1972 a vertical line was added to the left side, and the hub was not updated again until 1977, when the railing was fixed.
Wow, it is a 1976 D. I didn't think I needed the whole coin since it's most like a grease filled die. Learned something new today...thanks!
