Well I haven't seen Buffalo Gals yet. Also known by its earlier name, Lubly Fan published in 1844. That would fit nicely. Old Dan Tucker published 1843. Oh Susanna published 1848. The public love to discover that these familier ditties go that far back. A good source to date songs to see if they fit your time period is here:

www.pdinfo.com

It has an extensive list of songs in the public domain with publishing dates. A useful site is "History in Song" which can be found in the Mudcat links here.

Rex