Here's a list of Presidential Unit Citations awarded during Korea, many were issued during the retreat from the Yalu. Here's the site.
http://www.koreanwar-educator.org/topics/p_kwar_unit_citations.htm1st Provisional Marine Brigade (7 August-7 September 1950)
Tribute to 1st Marine Division Korean War Veterans
1st Marine Division (27 November to 11 December 1950)
HQ, 1st Marine Division, Division Memorandum No. 238-50, 19 December 1950 Operations in the Chosin Reservoir Area
Distinguished Unit Citation, General Orders 18, Co. K, 15th Infantry Regiment, 3rd Infantry Division (3rd Award), 10 March 1955
Distinguished Unit Citation, General Orders 923, Company A, 5th Infantry Regiment 5th RCT and the First Section, Machine Gun Platoon, 5th Infantry Regiment, 5th RCT
and Forward Observer Team, 555th Field Artillery Battalion, 5th RCT,11 October 1953
Commendation from Capitol Division, Republic of Korea Army, to US 987th AFA Battalion, 18 August 1952
Presidential Unit Citation, 65th Infantry Regiment, 3rd Infantry Division, June 1953
Presidential Unit Citation, 1st Marine Division, Reinforced, 21-26 April, 16 May to 30 June, and 11 to 25 September 1951]
Meritorious Unit Commendation, General Orders N. 243, 28 February 1953, to the 1st Loudspeaker and Leaflet Company
Distinguished Unit Citation, General Orders No. 35, Companies I and L, 35th Infantry Regiment, 25th Infantry Division, and Heavy Machine Gun Platoon, Company M, 35th Infantry Regiment, and 75-mm Recoilless Rifle Platoon, Company M, 35th Infantry Regiment, 8 April 1952
Presidential Unit Citation, 1st Marine Division, Reinforced, 15 September to 11 October, 1950
ROK PUC, HQ & HQ Co X Corps, HQ & HQ Battery X Corps Artillery, HQ & HQ Battery 5th Field Artillery Group, 50th Anti-Aircraft Artillery battalion (Self-propelled), 92d Armored Field Artillery Battalion, 96th Field Artillery Battalion, 8221st Army Unit Field Artillery Topo & Met Detachment, 2nd Engineer Special Brigade, 44th Engineer Construction Battalion, 58th Engineer Treadway Bridge Company, 73d Engineer Combat Battalion, 79th Engineer Construction Battalion, 185th Engineer Combat Battalion, 53d Engineer Boat & Shore Regiment, 4th Signal Battalion, 56th Amphibious Truck & Tractor Battalion, 15 September to 24 December 195
1st Battalion, The Gloucestershire Regiment & its supporting unit 'C' Troop, 170th Independent Mortar Battery, Royal Artillery
Naval Unit Citation, 1st Marine Division, Reinforced, 11 August 1952 to 5 May 1953 and from 7 to 27 July 1953
Distinguished Unit Citation, 2d Infantry Division and attached unit, Battery C, 937th FAB, 16 to 22 May 1951
Naval Gunfire Detachment of ANGLICO, assigned to X Corps to support the evacuation from Hamhung-Hungnam immediately following the breakout from the Reservoir.
Distinguished Unit Citation, General Orders No. 35, Companies I & L, 35th Infantry Regiment, 25th Infantry Division, and the following attached units: Heavy Machine Gun Platoon, Company M, 35th Infantry Regiment; 75-mm Recoilless Rifle Platoon, Company M, 35th Infantry Regiment.
24th Military Police Company, 24th Infantry Division, Meritorious Unit Citation
Headquarters & Headquarters Co. & Medical Co., 21st Infantry Regiment, 24th Infantry Division
24th Infantry Division and attached 441st Counter Intelligence Corps Team, 2 July to 15 Sept 1950
7th Infantry Division - ROK Presidential Unit Citation for period 8/1945-12/1948 and 17/09/1950-27/03/1951