Here's a potential interesting piece of history if only it could be conclusively identified. The seller believes that this prototype brass-bodied resonator may be the work of Charles Brasher.
Charles E Brasher was a Canadian inventor, metalworker and maker of stringed instruments in the early to mid 1930s. Inventions include a novel cone for the resonator guitar, patented in Canada in 1935.
Currently listed on eBay with a Buy It Now price of $1,499.