They look sort of like a logger decided to become a cowboy so he had his logging boots resoled and heeled!
The 'shelf' or sole edge doesn't hold up spurs, they rest on the top of the heel area. I don't know what to say... I have never seen anything like them before. The neolite top lift is a post-war material - very popular in the 1950s - 60s, so they might be a bit older. Neolite begins to disappear from use in the 1970s, so the boots might be 1950s/60s.