Phil - At one time I had quite a few old blunts that were organized into a collection, traded them off many years ago. The collection has some blunts made of wood. Don't really have knowledge of any advertisements for wooden blunt to be able to assign any dates. If you post a photo someone may recognize something about the blunt or the arrow.
There are also some wooden Popenjay (sp) points made of wood that look like a blunt, some are actually part of the arrow which tapers to a larger OD toward the point end.