Ron Guth: The date range for the Heraldic Eagle Half Eagle is from 1795 to 1807. However, the new reverse design did not actually appear until 1797. The reason for this apparent date disparity is that a left-over 1795 obverse die was used in 1797 as part of a cost-saving measure (the same thing happened in 1798, when an old-style Small Eagle reverse was used). Further cost-saving measures resulted in three overdates in this series, including a 1797 over 5, an 1802 over 1 (no Half Eagles were struck in 1801!) and 1803/2.
Mintages for this series range from a low of 7,451 (in 1799) to 64,093 (in 1806), though official mintage reports are not necessarily accurate and all years were subject to destruction in later melts when their intrinsic value exceeded their value was currency. Included in the Heraldic Eagle Half Eagle series are two unique varieties, both in the National Numismatic Collection at the Smithsonian Institution: the 1797 16 star obverse and the 1797 15 star obverse.
Though this type is scarce in general, all dates can be found in circulated condition with relative ease and a little bit of patience. Mint State examples are surprisingly plentiful, with over 800 examples listed in the PCGS Census as of March 2011. The most common Mint State grades are MS-62 and MS-63, where over 60% of the Mint State population appears. MS-65 examples are very rare. MS-66 examples are exceedingly rare, with only four examples graded by PCGS (one from 1800, one from 1802, and two from 1803).