This is a very early and rare original porcelain Mobil sign with rare detailed Pegasus. I read in past that this design of pegasus and facing left is pre 1920s. Sign has one side with pegasus the other with Gargoyl, The gargoyl side may have been towards the sun it has more wear and fading as shown The Pegasus side has more shine.
I think this may be foreign since the Spirit ones are usually not US ones. The item "Rare Vintage Original Mobil Early Pegasus Motor Oil Porcelain Flange Sign" is in sale since Tuesday, January 15, 2019. This item is in the category "Collectibles\Advertising\Gas & Oil\Merchandise & Memorabilia\Signs".
The seller is "gasoilsodasign" and is located in Hesperia, California. This item can be shipped to United States.