I'd say the odds of it being a real 500 are good: interior & trim seem legit.
Interior code on the fender tag should tell, as long as it's the real fender tag.
Broadcast sheets were different in that era; my '64 Savoy had a small sheet.
I'm not sure if the 500 got an engine-turned applique in the big side molding; regular Polara was painted there.
Does seem the glovebox door should be red inside.