A brief search didn't turn up anything...
I found on GMSV a modern looking US 25E cutout in Tazewell TN. Has anyone been by this location more recently...?
https://goo.gl/maps/dMHdAxTacPm
I did a quick search on the Rose Service Station and found at least one clear flickr image of this shield in 2010. It is definitely a custom install, more than likely by the owner(s) of the Rose Service Station, which is now a local museum. The original filling station was open between 1930 and 1956, which of course would have been during the time when U.S. 25E traveled along Main Street.