An 'Israel Moultrie' letter is found on this website. He evidently migrated to Liberia and wrote back through the A.M>E. church (missionary?).

Another link (from the AME Church) mentions a 'Rev and Mrs. F.J. Moultrie', who were excellent hosts (from the AME Episcopal Zion? church).
There is also a 'Robert Moultrie' and an Edward and Daphne Moultrie, fpc, in the 1861 Census of the City of Charleston, SC (table form - totals only).

There may be more. I didn't look at all the results, but do a search on the site.

I couldn't get into the other DB I usually search. Will check back later in the week to see what I can find there.

[Of course, you already know of Rev. Moultrie's service and records. Is 'Israel' the same person? ]