If you have a magnifying glass or something of the sort, you could possible get a date from it. I think I see 1769, but we will definitely need better pictures in better light. It also seems to be an English coin from the "REX" that would follow the old motto on the coin. If you had stable and well lit pictures, we could help you masses.
Harps are almost always Ireland. There are two for this year (1769), but I believe it to be the shorter (first link) https://en.numista.com/catalogue/pieces21907.html https://en.numista.com/catalogue/pieces11360.html
