Groceteria.com

This design looks like it predates even the "buggy" signs, let alone the Circle S parking sign!

http://www.flickr.com/photos/thedailysnap/179442610/

I would wager that that's a "one-off" sign meant to blend in with the neighborhood. As such, it could be of most any vintage, but probably early 1960's.

It's not unusual to see variations in signage or store design to fit neighborhoods or shopping centers. Williamsburg, Virginia is full of examples, as is the Richmond area and DC as well. For example the Safeway in the River Road SC in Richmond was built around 1960 and is extremely colonial in design and had signage that was gold on a green/black background - you can see pictures here: http://mysite.verizon.net/d.mcgrann/. I also remember going on a field trip to Williamsburg in elementary school where we joked about the "Colonial Colonial Store" that was in the old Williamsburg Shopping Center, though I'm not sure that was that much "colonial" in design.

This particular sign seems to me to be something I would expect to see in NW DC, probably along Massachusetts Avenue somewhere near American University.

I think I may have seen this one or one like it--in an area near Mount Vernon, VA called Hollon Hall. That area is known for distinctive modernist houses from the 50s that were built to emphasize views of their wooded surroundings. It also has more traditional buildings in its business district, which is a collection of strip malls. Much of that area was built as a planned community and some of it is landmarked. It's exactly where you'd find something like that sign.

There used be a Safeway on Massachusetts Avenue--it closed about 15 years ago. A sign like this would have fit in with that shopping district in what's known as Spring Valley. I forget what the Safeway became. The relatively small branch of Garfinkel's department store which anchored the area is now a flasgship Crate & Barrel.