The front and rear bumpers on the 1953 Henry J are not the same. They are both pointed and look almost exactly the same but the difference is, the rear bumper has a bumper bolt right in the center which the front one does not. The front bumper has holes for the license plate holder which the rear one does not. The 1951 and early '52 Js have a front and rear bumper that are the same but the late '52s and '53s do not. The late '52s have a pointed front bumper, same as a '53 but they have the flatter rear bumper like a '51.
The '54s were left over '53s so you'd have the same issue - rear one has a hole in the center, front one has two small holes for the license plate holder.
If you did find the opposite one and were planning on having it replated, the holes could be drilled / filled first, then plate it and it would probably look fine.