This retro looking Cosco model 11-120 red and chrome kitchen chair has a built in pull-out bilevel step stool. It's not the original 1950s version, but it looks pretty much the same. This one has a label underneath the seat listing the manufacture date as 2011.

The chair is about 35 inches high at the padded seat back. Front to back depth at the legs is 14 inches. The top step of the stool is 17-1/2". It's in super clean condition with shiny chrome and no damage - it obviously wasn't used much if at all.