I have planned a trip to China for Chuseok. Is it at all possible to get a tourist visa if my ARC card is not ready in time?

It is hard for you to get a tourist vsia if your ARC card is still being processed, you can try to use the Receipt to prove your ARC is in process for China visa application, you'd better call one of the travel agencies authorized by China embassy/consulates in Korea to enquire it.