I doubt you will find a match, but what do I know.

To find the exact date, take it to a lighting expert, someone who has done lamp repair for decades. I believe it might be easier to date the hardware than the shade and painted design.

My first reaction is that it's an early Art Deco transitional design (1920-1925) and most dealers, I think, would list it as Art Deco. The design is reminiscent of architectural details from 1917-1921.

However, it also might be derived from Native American or even Mesopotamian design, these influences are seen in later details, from 1938-1945 and even again in the early 1950s.

Much of the vagaries of these types of details are completely lost on dealers, who really expect the collector to know the patten name, etc. So god knows how a dealer might list it. Please don't make me try to get into the mindset of an antiques dealer.