Stumbled across this post and I always try to be able to tell fakes from originals so I began to search. Your sign appears to be authentic. If you will go to ebay #400416085019, it is a reissue. It does not have the markings your sign has. Also the blue is a lighter blue where the originals are more black. I am also going to post something I use as a good guide on knowing fakes.
Other than knowing a specific maker's name on an item is as false as the item it is printed on, another quick way to identify contemporary printed metal advertising signs as new is to examine them for the method of printing used. If a modern photo reproduction printing process has been used to make an item the familiar honeycomb-like dots from which such a process creates images will be present and can be seen for certain when viewed under magnification. The modern printing pattern of dots may often be seen with the naked eye, but use a loupe or similar magnification tool to check a metal advertising sign for them if you are uncertain. Older methods of printing that were generally in use at the time original old advertising signs were made won't display a halftone dot pattern like modern prints. When we go to swap meets are a buying trip we carry a jewelry loop with us. Reissues that are painted when viewed under a strong loop will show honey one dots are better known as matrix dots. Try it on a reissue and you can see. This however will not work on the porcelain reissues.
Mike and Debbie
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