Thats only 700 RPM over the rated max, so I guess it's possible without floating the valves. It's also well on the downward curve for HP and torque, so there's not much use going that high. That said, with the 4-bolt mains, pink rods and forged steel crank, I doubt if he did any damage - as long as he didn't do it every time he drove the car.

I'd suggest a compression and/or leak-down test before buying the car.