Probably. It would be hard to be certain with the single photo, as there are other antebellum US bayonets with socket mortises that look like that, but more than likely it is a M1816, M1822, or M1827 bayonet.
It is claimed it is a battlefield pickup bought from an estate sale that claimed it was a battlefield pickup. All I know and he knows. Certainly looks the part.
Yup, you can find plenty of 1816 bayonets in nice condition and they aren't terribly expensive. I picked one up for my 1816 without having to look too hard.