I think this photo shows the ad Jim is referring to:
Rooks Cantina 505,
282 Fourth St.
September 28, 2014
credit: Nancy Knisley
The ad, on the dark brickwork on the right, is rather faint, but I believe that the larger letters say "WALLPAPER." Above that, among the smaller lettering, I think I see "OUSE" (house?) and very faintly, "PAINT."
Laman's Wallpaper & Paint was once at 294 Fourth St., but I don't know if the ad was for that store or not.