Posted 14 March 2012 - 10:54 AM
My educated guess is that the bridge base is a "Ventura" copy of an inlayed Gibson base. The inlay doesn't look quite right to me, and the base itself looks a little bigger and "bulkier". Since the bridge base on an archtop has to be (should be) custom carved to fit the arch of the guitar for which it is fitted, it is unlikely this is a authentic Gibson bridge base, for it would have had to be re-carved to fit this guitar. In addition, Gibson archtop bridge bases generally have the serial number of the guitar for which it was fitted written on the bottom, and the bass and treble sides marked.
As for the TOM, there was an era when Gibson was using nylon saddles, and someone just put a real Gibson Tune-O-Matic on the guitar. They may have wanted the intonation adjustability of the TOM, or maybe wanted the "deadening" effect of the nylon saddles on the archtop. When the Japs starting making quality copies of American guitars in the early 70's, they were building them to American specs, many with American hardware. To "upgrade" hardware was just a drop-in replacement.