The trim ring is original in my opinion but I think you have an issue with that complete hood being original.
No one ever made a reproduction underside tub for the shaker conversion with these factory stamping 'wrinkles' at the front, and also found on the sides of a real tub.
Repros tubs are smoother all the way round.
On some original underhood tubs, the wrinkles are more prominent than others.
First picture here is an original Cuda hood, second picture is an original Challenger hood.