Israel's selling advanced weapons to the PRC is the surest way to lose a friend. I'm going to be watching this closely from here on out.
Israel doesn't give these countries squat. The technology that we call "advanced" is 1980's technology to Israel.
I lived in Israel for a while in the 1980's. My firends were in the IAF and used to joke about how out of date the systems were that the US sent to Israel. They would rip them out and put in their own.
Anything Israel is sending to China, the US more than likely already knows about it and has effective countermeasures for it.