These Wade and Butchers, with the stamp "Blank for Concaving" are not that rare at all. Geo Wostenholm made some as well http://straightrazorpalace.com/razor...abay-fake.html. My guess is that these were sold as is to street grinders and third partys to finish.
This particular razor grinding doesn't look like it was done professionally at all, and the scales don't match the time period, or the blade at all. The only thing its got going is it large size.
Somewhat sad that someone will pay that much for a razor that probably has some geometry problems.....