Though it was said to be inspired by an early bowie knife in the collection of the Smithsonian Institution, the bowie knife designed for "The Iron Mistress" (1952) is not representative of any authentic example that we know of. Nevertheless, its design appealed to many people and it remains available from various makers today. Gil Hibben said he was inspired to become a knife maker by the 1952 film and still makes several versions of the bowie in that style.
Knifemaker Bo Randall anticipated a market for a bowie-style knife after the film and decided to make his own version. He contacted a friend who ran a theater in Orlando and got a frame from "The Iron Mistress" from which he made a 5” x 7” print for reference. That print is still on display at the Randall museum, and the knife designed from it is called the Smithsonian Bowie.
In 1957, Randall contacted Alan Ladd requesting the actual dimensions of the movie knife. Ladd responded personally, and gave the measurements as “Total length of knife -- 16 inches, blade -- 10-1/2 inches, handle -- 5 inches, width of blade -- 2-1/2 inches, blade thickness -- 3/8 inch, and guard between blade and handle -- 3-1/2 inches.” These measurements were close to what Randall had extrapolated from the movie scene he had worked from.
The "Iron Mistress" continues to inspire knife makers, as evidenced by these examples created by Steve Voorhis:
There is more information on the Iron Mistress bowie in a 2007 thread at Blade Forums.