Marc,
I searched for a really nice example of the Willys rear bumper for years. The only luck achieved was an OEM piece that was supposed to come from a Jeepster... it had no Willys imprint however and it didn't have the same curvature at the ends as the original on our wagon. If you look at the first picture you can see the difference. Why am I telling you this? I suspect there is quite a bit of variation in the production of these original bumpers - how do you know one you find will truly fit properly?
The other pictures show the imprinted "Willys" on the original (heavily used/corroded) bumper of our wagon.. it fits better but you will notice the imprinting is really poor. Since it seems you have already gone to the trouble and expense of having your bumper rechromed, what about getting a Willys sticker from a sign shop and enhancing the look of what you already have? Another possibility of course is to get a reproduction and cut the Willys script into the surface using a laser engraver... and then having it chromed or painted.
Cheers,
Pavel up North.
