Here's the full details, and it took the better part of two weeks to sort this all out, piecing together information from various sources. What we're looking at is a watch commissioned as a commemorative gift for one of the directors of a 1970s TV show:
Eagle 1 does indeed refer to the spacecraft from the classic TV sci-fi show, "Space 1999"
P.S. refers to the U.K. production company, Pinewood Studios. R.S. refers to Rose St., which is the street along which the two sound stages used for filming, L & M, were located.
IT refers to Italy, 4PD is either "for Peter Duncan" (a cast member) or "for the Producer Director" and 76NO is November 1976
The original owner was an Italian antiques collector who bought it while travelling in Italy. He picked it up in Aarberg, which is very near the Gallet workshop in la Chaux-des-Fonds. It seems as if whomever it was originally made for, they never collected it, or if they did, it didn't leave Switzerland until the Italian collector took it back to Italy.