Two weeks only, reject the car perhaps?

Depends what they mean by the "pin", it could be the axle on which the wastegate flap moves.

If it's faulty (for example, bent or some other manufacturing defect), the wastegate will tend to stick in one position, so exhaust gases are bypassing the impeller blades and the turbo will not generate sufficient boost. Or it could be sticking shut, causing overboost and the ECU is putting the engine in limp mode.

Most modern turbos are not available from dealers as individual components, they are supplied as a complete turbo / wastegate unit.

Hopefully it's a one-off defect, and the replacement turbo will be fine. We've had a couple of Puntos over the years and both have been very reliable, despite being driven in the harshest conditions (i.e. by my wife, the Michelle Mouton of Macclesfield). Good luck.