I'm no lover of patina/damage/degraded dials, but in this case I agree with the other posters. The majority of the dial is pretty much intact. It only seems to be the lighter coloured pulsations inner circle that has suffered noticeable degradation. You will look long and far to find a dial restoration specialist who might be trusted to restore that part of the dial to factory spec in such a way that it does not look out of place with the rest of the dial ageing.