I'd like to get some ideas from the gang on the forum about the value of this NOS GRAI-PENN Motor Oil sign. Not much to be found online about this brand, or the sign.

This NOS painted tin sign measures 15" wide by 20" high. Excellent condition, with very good color. The large "GRAI-PENN Motor Oil" lettering is embossed. The oil can pictures indicates that GRAI-PENN is a product of the Viscosity Oil Co., Chicago, Illinois and Oil City, Pennsylvania, established in 1892. Thanks for any help! John
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