Just request a couple of bulbs from PS Audio. They will send them to you at no charge. I did that a while ago.
PS Audio P300 logo light bulb
I bought a used PS Audio P300 AC regenerator and like many units the PS logo light was out (not even a dead bulb in the socket). I know I can probably buy a new one direct from PS Audio because it is a common problem, but I would like to find out what type/model of bulb is used and were to find new ones. Anybody have this information?