It's late but I thought it a good one to post still because of how hard of a time I am having finding another like it or any information on this sign at all.
It is a A frame sign without a date mark and has metal tabs sticking out to hold topper signs in front of the wording on the back. There is also a removable bar going up each side of that side.
It's roughly 5 feet tall and 36" wide.
I just found a original SoCoNY-Vacuum Map pack with the same wording and Font on it and it is dated 1940!