These are noticeably smaller in size than the silver 8 reales of other nations. Also they were clearly struck from a debased silver. Due to the size and current finds, it's my guess that these coins were struck solely for domestic circulation.

The Haitian Revolutionary Calendar started from 1 January 1804, this being Year 1.
So the coin date of AN 27 should correspond the the Gregorian date of 1830.