While reading several books on the Battle of the Chosin Reservoir (mainly using The Last Stand of Fox Company as a reference), soldiers claim to be facing Chinese soldier armed with a vast variety of different weapons. Type 24 rifles were apparently the "standard" infantry rifle for PVA soldiers but the marines account facing soldiers armed with Japanese arisaka rifles (both in 6.5mm and 7.7mm) Mosin-Nagant rifles, copies of the Thompson Submachine gun, russian DP machine guns, Type 50 sub-machine guns, and some belgian top loading infantry machine guns similar to the BAR (can't remember the exact name) etc. While I could understand arming primarily real echelon troops with non-standard equipment I can't understand the reasoning for arming front line units with so many different weapons that require different ammunition, especially if they were deployed specifically to assist the North Korean forces against the UN coalition. Was the Chinese supply train simply that good that they could provide all the different ammunition types for these troops or did china simply not make any effort towards standardizing it's military and just gave their soldiers literally anything that would go bang?
The Type 24 was a standard issued rifle to Republic of China troops beginning in 1935. The Communists captured many ROC supplies during the Civil War.
The Arisaka rifles were captured from the Japanese and from the Manchukuo armies during and after the end of the Sino-Japanese/World War.
The Mosin-Nagant rifles and the Type 50's would have been supplied by the Soviets during the interwar period.
The Thompson copies and American weaponry would have been captured from ROC troops during the end of the Civil War.
It's important to remember that for most of the first half of the 20th century, China was at war. When the Communists took over in October of 1949, they had been fighting for nearly 30 years. With the Korean War beginning 8 months later and the PRC still pacifying the country and eyeing the possibility of an attack on Formosa, there was no time to build a new and well equipped professional military. As the great Donald Rumsfeld so eloquently put it, "as you know, you go to war with the army you have, not the army you might want or wish to have at a later time."
During the Chinese Civil War, the ROC military was losing so many supplies to the Communists that the US military advisors said that with losses about to surpass 50%, the US government was, in fact, supplying the communists and that it might be wise to stop supporting Chiang's troops. Also, during WWII, both the ROC and the Communists were happy to hold the line against the Japanese and allow the US and the Allies to do the heavy lifting. The point is that the Chinese are a very shrewd people and by scavenging over 30 years of conflict, the PRC went to Korea with a wide range of effective weapons.
In short, the People's Volunteer Army was supplied with anything that would go "bang," yes.