I have no historical information about Boudon, they were in business from at least the 1890s to the 1920s.
Like British pianos of the period, many were either made for retailers by wholesalers, or small firms would buy in ready-made parts and build the pianos from them, so they look very much alike.
By the 1860s, many pianos like this were made by Bord, Erard, Elcke and Pleyel, and imitated by lesser-known makers.
I'm not fluently in english,I hope you will able to understand me ...
I recently see a A.Bord Piano, sn 101679, with the same name of Piano manufacturer, and I find this about B.Boudon
He beagn to work on 1891