It's a nice mid grade dollar from the (tougher) early Seated Liberty era. I'm no expert in this series, but it seems the 1859-O and the 1860-O are among the most common dates for the type. If you want one specimen in mid VF then I would recommend that you keep this 1843 one! If you want to upgrade to a higher grade one, like a nice lustrous AU or even a low MS then 1859-O and 1860-O seem to be the best bet. The
Seated Liberty dollar with the motto on the reverse is the only major silver dollar type coin I'm missing, and for the without motto one, I specifically wanted the 1840s because this decade features many non key dates that are still far less common than the typical "type coin" speciments. I ended up upgrading my 1842 dollar for an 1841 in a slightly higher grade, and while my coin is a "type coin" for me, I like having it be far from the most common dates of the series.