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You might like this from Google Books....can be read online.
Sorry for the very late response and thank you for the information
Dear Mr. Gonyea,
Thank you for posting your request on History Hub!
We searched the National Archives Catalog and located two series titled Records Relating to Korean War and Early Cold War Operations and Training, 1948-1962 and Korean Command Diary Files, 1950-1954 in the Records of the U.S. Marine Corps (RG 127) that contain records related to various Marine Corps unit activities in Korea, both during and after the Korean War. For information about these records, please contact the National Archives at College Park - Textual Reference (RDT2) at email@example.com.
Due to the COVID-19 pandemic and pursuant to guidance received from the Office of Management and Budget (OMB), NARA has adjusted its normal operations to balance the need of completing its mission-critical work while also adhering to the recommended social distancing for the safety of NARA staff. As a result of this re-prioritization of activities, you may experience a delay in receiving an initial acknowledgement as well as a substantive response to your reference request from RDT2. We apologize for this inconvenience and appreciate your understanding and patience.
You may wish to consult the unofficial website Records of War that has some records related to Marine Corps unit activities during the Korean War and are available online.
We hope this is helpful, best of luck with your research!
I went to https://www.koreanwar2.org/kwp2/usmc and the page has a long list of various options to choose from. I was able to scan down and find "5th MARINE REGIMENT - 1ST BATTALION - HISTORICAL DIARIES", which was the group my father, Edmond Kuenster was in during the Korean War in 1950-1951. It had monthly diaries for about a 4 year period. But this website had many more historical sites to select. Maybe you can find something your looking for there.