The shear pinis the weak link in the system. It's designed that way on purpose. When the system gets near it's breaking point, the pin shears, and the engine quits before any damage can be done.
You can always put in a stronger pin. Put in two pins. Heck, you could just weld the gear to the shaft. Or, you can figure what's putting all that strain on the system, and change that. For example, if you have a HV/HP pump and use straight 50
oil, maybe that's not such a good decision.