Jim Hendershot is probably right when he says he will get as many
numbers as there are answers!  Things were not standardised even in
Europe at that time, never mind in America.

In Britain from 1846 to 1854 the Philharmonic Society pitch of
A=452.5 Hz was quite often used, except by the famous British piano
manufacturers, Broadwood's, who recommended and factory-tuned their
instruments to A=445.9 Hz.

In Germany things were just as confused.  Johann Hummel wrote in
1827 ("A Complete Theoretical and Practical Course of Instruction on
the Art of Playing the Pianoforte", published in London) that there
were different pitches in Dresden, Vienna, Berlin, etc., and that
different pitches were used in the chamber, the theatre and the church.
In 1834 the Berlin Opera used A=441.8 Hz while the Opera in Dresden
used A=435.  In France in 1836, the Italian Opera used A=437 Hz and
the Grand Opera A=441.  In Austria the pitch rose steadily from 1780
(A=421.6) to 1834 (A=456.1).

In 1859 the French Government fixed a standard pitch of A=435 Hz,
which went a long way toward standardising things.  As late as 1899 in
England the pitch was generally much higher, but in that year it was
decided to adopt the (lower) New Philharmonic Pitch (A=439).

Fortunately, Jim need not go into Mean Tone versus Equal Temperament
tuning, as this was resolved by the time his instrument was built, even
Broadwood's adopting Equal Temperament, rather later than many other
manufacturers, in 1846.

(Source: The Piano-Forte by Rosamond Harding, Gresham Books, 1978)

By and large, I think I'd tune it to A=440, on the basis that it's
maker may well have set it higher than this when it was made!

Best wishes!

David Evans
Mechanical musical instrument restorer