I have said that the movies of the 1930s and 1940s, especially westerns and detective movies, are filled with some of the best Bit Actors and Actresses. Here are some suggestions for the next decade.
There were many transitional films being made in the 1950s. Filmmakers were still using a lot of black and white film to help lower the budget. There was a plethora of WWII movies, as the war ended only five years before. Television was really getting started, and some actors were being drawn to it, while others who started in TV were trying their hand on film.
James Garner (b. 1928) has always been one of my favorite actors. Other blogs will cover him, but let's look at his work from the early days.
Garner started on the 95 tiles he has listed on IMDb in the 1955 - 1956 TV series, "Warner Brothers Presents." That show rotated three story lines and had some regular characters for each story. One of those stories was "Cheyenne" which went on to have it's own series.
His first movie was Toward the Unknown also in 1956, starring William Holden (1918 - 1981), about the early test pilot days of the space program. Look for a six year old Jon Provost (b. 1950) in it, before he landed his major role as Timmy Martin on "Lassie." This was Provost's sixth film after starting his career in acting at age two.
Also in 1956 Garner was in The Girl He Left Behind. Listen to this cast...Tab Hunter (b. 1931), Natalie Wood (1938 - 1981), Jim Backus (1913 - 1989), Henry Jones (1912 - 1999), Alan King (1927 - 2004) and David Janssen (1931 - 1980). There must have been some bit actors as well!
The next year, 1957, Garner was in Shoot-Out at Medicine Bend starring Randolph Scott (1898 - 1987); Bombers B-52 with Natalie Wood, Karl Malden (1912 - 2009) and Ephrem Zimbalist Jr. (b. 1918); and then in Sayonara starring Marlon Brando (1924 - 2004).
In 1958 he gets star billing in Darby's Rangers. In that one we also see Edd "Kooky" Byrnes (b. 1933) who worked with Garner in movies and on TV. Byrnes has 82 titles on IMDb and is a worthy Bit Actor.
Two more films wrap up Garner's work in the 1950s, Lafayette Escadrille (1958) also with Tab Hunter, and including a part for Will Hutchins (b. 1930), TV's "Sugarfoot." Garner is uncredited in Lafayette Escadrille, and then he gets top billing again in Up Periscope in 1959. Up Periscope also includes Edmond O'Brien (1915 - 1985), Alan Hale Jr. (1921 - 1990) before he was ship-wrecked on "Gilligan's Island," and football great Frank Gifford (b. 1930).
That's a lot of good work for one decade, and if you can find the movies, they are all good to watch. Just pay attention to the little parts!