Aftermarket oil pump gear on Nissan sr20vet

Does it make any sense of using aftermarket oil pump gear on sr20vet?

Depends on what you're doing, and whether it's a sintered gear.

Don't know about that specific engine, but most manufacturers use at least one sintered (powder) gear and these can break under 'performance' conditions, if it does break you'll lose oil flow and pressure and potentially destroy the complete engine.

I figure it's cheap insurance to remove the risk, especially compared to the cost of the possible rebuild.