Astor Plaza -- This is an artist's drawing of Astor Plaza, newest Park Avenue business project announced by Vincent Astor. The 46-story, metal and glass project will rise between 53rd and 54th streets and will have a block-long plaza on Park Avenue. Estimated cost is $75,000,000. The project will encompass one million square feet of office space. September 19, 1956. (Photo by AP Wirephoto).;Astor Plaza -- This is an artist's drawing of Astor Plaza, newest Park Avenue business project announced b