When it was time to close the shop, Jiang Chen told the customers since the quantity of Doctrine Artifacts was limited, he would only sell them to proper customers. For example, he would not recommend a knife to a swordsman.
As to the quantity, he would sell three pieces every day. And he did not accept reservations. In fact, the Doctrine Artifacts Jiang Chen had could have even allowed him to build an arsenal. He had gotten all of them from the Heavenly Palace by defeating the divine soldiers and divine generals. The Doctrine Artifacts assumed a normal look after being processed by Jiang Chen.