Depends on what you are trying to represent, an imported fowling piece or a colonial piece made in the British style. There were British style fowling pieces made in the New York City, Long Island sound, Connecticut area which were most often stocked in maple and they had carving sales which were quite elegant yet (I think) distinct from English guns. As noted the majority of English imports were stocked in English Walnut.
The confusion on this topic comes from suppliers who make "English fowler kits" with maple as the first choice, and English walnut rarely offered at all. Don't try to learn anything from most catalogues.
