I just commented that it *could* have been, but when I cleaned it, there was also a residue of the gold chromating... so I suspect it was 'spray bombed' before I bought it in '76, and then I do remember 'touching up all the black'.. hot rodder that I was..
I'm fairly certain this is the original booster; the two owners before me were not 'car people' (a teenage girl and an undercover policeman - who had it only a short time). The car had been kept washed/waxed and cleaned (appearance wise), but there had been little maintenance done in the '60K or so miles it had on it when I got it. Of course, there's no way of knowing 40+ yrs later, or even 7 yrs later, when I purchased it.
Note: The dates on the brake switch (9-199) exactly match the julian date on the booster; the master cylinder was dated 175... further making me believe all those parts are original to the car, as was 99-100% of the parts when I purchased it.