Dear Mr. Wilhelm,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog for moving images of the P-38 from 1940 through 1949 and located multiple films and still images.. We also searched the National Archives Catalog for Richard Bong, and located the Official Military Personnel File for Richard I. Bong which has been digitized and can be viewed online through the Catalog, a well as multiple films and still images.
Please contact the National Archives at College Park - Motion Pictures (RDSM) via email at firstname.lastname@example.org for more information about our motion picture holdings and contact the National Archives at College Park - Still Pictures (RDSS) via email at email@example.com for more information about our photographic holdings.
Other institutions which may have holdings of interest to you include the Air Force Historical Research Agency, National Museum of the United States Air Force and other Air Force and aviation museums.
We hope this information is helpful. Best of luck with your research!