The Haiyou Store at the east end of Dongguan Street specializes in drama, ethnic, performance costumes, and tools.
There is a music performance store on Wenhua East Road, 100 meters to the west opposite Shantung University. It has a full range of clothing, but I forgot to name it. The place is easy to find.
I don’t know where you live, but I’ve provided two places, go check them out nearby: P)