He highly doubted that the Kaddar Region possessed the wealth to purchase a weapon that powerful, given that the nations weren't exactly economic powerhouses in a broad sense, they probably did not have access to the means to build or acquire such a super weapon.
Since that was the case, Rui was inclined to stay. The benefits of the Floating Sect were great, he hadn't even been there long but he felt as though his body had grown stronger after being strengthened and nourished under extreme conditions.
One of the reasons he was especially determined to make the best of the Floating Sect was because of the reveal of the breakthrough to the Senior Realm. He now knew that one of the conditions for reaching the Senior Realm was having a body capable of withstanding the power of the Martial Heart.