The 1863 Dime had a mintage of only 14,000 coins, the smallest Dime mintage since 1804! As a result, this date is extremely popular with collectors and it can be very difficult to locate a nice, problem-free example. Fortunately, a small number of Mint State examples exist, including some nice Gems. In fact, the PCGS coinFacts Condition Census begins at MS65, then tops out at MS66+. NGC has certified two MS67 examples.
Gerry Fortin identified only one die pair for this year. What's interesting is that the same dies were used to make both Proofs and circulation strikes.