From Sellers:
Nathaniel N Wilmot
Boston 1847-1849
St Louis 1850-1859
St Paul 1862-1864
imported shotguns

Vorisek does not list him.

From the 1850 Census, St Louis
Nath Wilmot M 49 England (his trade is illegible, not a gunsmith)
S H A Wilmot F 29 England
Harvey Wilmot M 6 Mass
Emma H Wilmot M 5 Mass
Sarah Ellen Wilmot F 10 England
Ann Kellan F 18 Ireland
S N Wilmot M 46 England Printer

View the Census page
He is at the bottom of the page

Pete