I'd like to research the manufacturer, although I'm fairly sure that it is Fulton.
Fulton was the "house brand" for the United Hardware and Tool Manufacturing Company, a hardware wholesaler, but is probably best known as an early tool brand sold by Sears Roebuck. In the pre-Craftsman days, Fulton appeared to be the most popular tool brand offered by Sears, and even after Craftsman had become well established, Sears continued to carry Fulton tools as lower-cost alternatives.
Fulton tools were likely made for United Hardware by a contract manufacturer, and the great similarity between some Fulton and Craftsman tools suggests that the same manufacturer later produced tools for Sears.
http://www.tias.com/8600/PictPage/3923468803.html this is a link to an antique tool site listing a similar but smaller Fulton Block plane.
G. Michael