I'm guessing it's the original finish, getting rid of all the dark finish so uniformly would be nearly impossible.
It says it was owned by the Hollywood Entertainment Museum (why they had it they don't say) so maybe it was a custom job for some big shot.
I have all the internals for one of these including a NOS CRT.
I fired up the chassis one day and it produces a wickedly scary amount of HV!
It's 54 miles and one Hernia away from me.
