The stable tunneling dynamics in non-Hermitian quantum systems is one of the fundamental issues in the study of quantum transport. Nonreciprocal coupling, as another crucial manifestation of non-Hermiticity, exerts significant regulatory effects on the stability of quantum devices and spin tunneling dynamics. Here, we place spin-orbit coupled bosonic atoms in a double-well potential with gain and loss, investigating the effect of nonreciprocal coupling on the system dynamics. Through analytical analysis of the Floquet states and quasi-energy spectrum under periodic driving, we obtain the \calPT symmetry phase diagram of the system. We further explore the synergistic regulation mechanism of multiple factors, including the strength of nonreciprocal coupling, the non-Hermitian strength arising from gain–loss, and periodic driving—on stable spin-flip tunneling. The results demonstrate that precise manipulation of nonreciprocity and gain-loss can significantly expand the stable parameter region of the system. In nonreciprocal systems with balanced gain and loss, the continuity and discreteness of the stable parameter region are determined by the parity of the driving frequency ratio \Omega /\omega, and the spin-flip tunneling can be precisely controlled via the parameters λ and 2\varepsilon /\omega . For the unbalanced gain-loss scenario, the equilibrium conditions for achieving stable spin-flip tunneling under different parities of \Omega /\omega are further provided. These findings offer a new theoretical approach for realizing robust spin-flip tunneling, provide guiding significance for the study of quantum state transport in non-Hermitian ultracold atomic systems, and also serve as a reference for the experimental design of novel spin-based quantum devices.