Ephemera can also be found through the search box. Advertisement, poster, trade, bill, programme, etc are all fruitful terms.
This is another excellent site where ephemera play their part in telling the overall story. The images are accompanied by descriptions, often providing context.
Browsing if free but this is, of course, a commercial site, selling high-quality prints of an impressive range of museum images in various sizes, framed or unframed, on canvas, etc. Users can log in, create My favourites, and a Basket.