The Institute of Heraldry is the authorizing agency for all military insignia. During WW2 the function was assigned to the office of the Quartermaster General.
On the website many of the unit insignias have been digitized but not nearly all of them. Still it is the place to go to inquire about insignia.
The Institute of Heraldry Home Page
THE INSTITUTE OF HERALDRY HISTORY
The Institute of Heraldry, U.S. Army, is located at Fort Belvoir, a military installation within the metropolitan area of Washington, D.C. The staff consists of thirty-two civilians.
The mission of the Institute is to furnish heraldic services to the Armed Forces and other United States government organizations, including the Executive Office of the President. The activities of the Institute encompass research, design, development, standardization, quality control, and other services relating to official symbolic items--seals, decorations, medals, insignia, badges, flags, and other items awarded to or authorized for official wear or display by government personnel and agencies. Limited research and information services concerning official symbolic items are also provided to the general public.
Heraldic and other military symbols have been used by the military forces as well as other organizational elements of the government since the beginning of the Revolution. However, until 1919, there was no coordinated, overall military symbolism program. In that year, within the War Department General Staff, an office was delegated the responsibility for the coordination and approval of coats of arms and insignia of certain Army organizations. In 1924, formal staff responsibility for specific military designs was delegated to The Quartermaster General. As the needs for symbolism by the military services and the national government expanded, the scope of the services furnished by The Quartermaster General’s Office evolved into a sizable heraldic program. The acceleration of activities brought about by World War II, the expansion of the Army, and subsequent increase of interest in symbolism, contributed to the growth of the program. In 1949, the Munitions Board, acting for the Army, Navy and Air Force, directed the Army to provide heraldic services to all military departments. The program was expanded further as a result of the enactment of Public Law 85-263, approved September 1957, 71 Stat. 589, which delineates the authority of the Secretary of the Army to furnish heraldic services to the military departments and other branches of the federal government.
The Institute of Heraldry was established in 1960 at Cameron Station in Alexandria, Virginia. Within the Institute, functions formerly performed within the Office of The Quartermaster General and several field activities were consolidated. Upon reorganization of the Army in 1962, responsibility for the Heraldic Program was assigned to The Adjutant General’s Office. In 1987, with the realignment of certain Army Staff agency functions, the Institute was transferred to the United States Army Human Resources Command. In April 1994, The Institute of Heraldry was relocated from Cameron Station to Fort Belvoir, Virginia. As a result of a realignment in October 2004, responsibility for the Heraldic Program was assigned to The Administrative Assistant to the Secretary of the Army, Resources and Programs Agency. Visit our web site at http:\\www.tioh.hqda.pentagon.mil.