I know the place you mentioned. Every time I go there to play, I will go in and have a look. The rain stones there are all real, but the prices are a little more expensive than those outside, and some are much more expensive. If you buy less, you can buy it there. If you buy more, you can go to Confucius Temple or Yuhuatai Martyrs Cemetery, where many are really cheap.

If you are satisfied with the answer, please adopt, encourage and help others. It is not easy ~ ~ ~