I noticed on your web page was written "The Marines of WWII and Korea were not issued leggings to be worn with utilities." Not so, at least my experience.
My reserve unit was activated in August 1950 and the next month found us at Camp Pendleton, Calif, where we were issued leggings. I have attached a photo showing me and 3 buddies at Tent Camp 2 wearing leggings under our barely visible bloused utilities. From a few photos I have, I am also shown wearing them for formal events with dress greens, but also some times no leggings while in utilities, so I guess they weren't worn for all events.
I don't remember when we stopped wearing leggings, but I don't remember wearing then while in Korea in 1951, nor any time subsequent to the war (I served three tours of duty, to 1959).
Hope this helps.
Victor R. Rolando