Grimes light gasket is also its base

I removed the Grimes lights today so I could sand the roof. The vehicle is 51 years old. The gasket is also the base of the light.
I'm wondering how expensive it would be to find someone with a 3D copier.....unless someone has a more realistic idea on how to replace these. The rubber edges are solid with no flexibility. Thoughts/suggestions always appreciated! There should be two pictures showing....... Thanks!

photos....

Here are the pictures......

Gaskets

Do you have a pic of the gasket. Metro has some universal U channels and others.

https://www.metrommp.com/index.cfm?f=part_list_by_type&Type=U-Channels

Kevin, just have to say how good it is to see this soul being restored. Well done!!

The original base gaskets were solid white rubber and produced for Miller Meteor by Federal Sign & Signal Company. When John Dorgan was alive, he sold some white rubber U channel that acted like a gasket for the lights. I don't know of anything available today for a gasket. One of the main problems with the solid gaskets that M M used was that it held the water under the gasket, leading to the roof metal rusting underneath the lights.

Have you tried DCaptain.com? The website is not up to date, but as far as I know, he's still in business. He may have something you can use.

Fairly nice job on Grimes light gasket

These pieces are stiff in places and floppy in some thanks to all the vertical cracks. I covered them with one-step auto body filler then sanded. The cracks come back when the piece is handled. So I then got a can of Flex Seal (white) and put two applications on each. I think everyone has seen this advertised on TV. It comes in a spray can and also comes in a small can.
Despite being touted as rubber, it goes on very watery so I elevated the pieces so they wouldn't stick to anything (well, I did it on cardboard first and learned a lesson). Plan on letting this dry for a day. I think from a few feet away they look good.

There is a product by 3M for the plastic bumper covers. You can sand it and paint it. If that doesn't work