That guy who sells the new steering clutch discs General Gear has them I believe.
Just make sure it is the right size, I bought two of them from General Gear about 10 years ago for my D4 7J and haven't got around to fitting them yet, but saw them in my parts box 2 days ago in their plastic bags sitting next to the old beat up originals that were on the tractor, and noticed for the first time that my nice new shiny ones are smaller than the originals, all these years I had never had them side by side!
It appears they have one but will charge for the labor to disassemble the radiator to remove it plus the price of the tag. Looks like I'm back to the old drawing board.
Make a top die reverse of the lettering and press the metal into a piece of urethane . Not all that difficult to do yourself.