This stamp “ Paysage Vendéen” represents a maraichin (the inhabitants or farmers of the marshes) in the bow of a bourrine (yole vendéene).
Aak to Zumbra a Dictionary of the World’s Watercraft gives for the craft:
YOLE VENDÉENE: Light fast pulling wooden boat used on the France Westcoast. Shallow, flat bottomed river craft of the Vendéen area. Cross planked bottom turns up at bow and stern; bow sharp or with a small bow transom; stern wide; often with coverboard; straight vertical or flared sides.
Length ca 4.5m, beam 1,25m, depth 0.35m.
More on the area is given on: https://en.wikipedia.org/wiki/Marais_Poitevin
France: 1965 0.95Fr. sg1687, scott 1129.