Has China acquired a large force of Backfire equivalents or are we just talking missiles?
China operates a large fleet of modern build Tu-16 copies, probably about a hundred now, that have the ability to carry a half dozen weapons in the ~3000lb / 1500kg range. As far as I know that is the top notch that they have bomber wise. The most effective anti shipping missile that I know of is a meter long extension of a copy of a Krypton type ARM. Probably deadly, but probably less edgy than a Kh-22.