But I believe your picture depicts a 3998J with unique dial 
My understanding is the text on that one translates to “Helmut Newton” as the commissioner was a big fan.
Below 2 are both J with different text dials (both likely to same owner as they were sold at Sothebys in the same one collection auction):
Additionally there was a 3998T (also in the same collection) with different text again on the dial:
I assume the P in this thread was commissioned by the same gentleman… now, was there an A and a R made as well? Or just a T, a P, and two J’s??