This framed picture shows what you can do with the postcard-size French Advertising images.
Here the Au Bon Marche postcard sheet has been printed onto smooth 225gsm white card and cut out with a craft knife and ruler.
It has been framed in a standard frame which takes an 8" x 6" (20 x 15cm) picture which came with a mount with a 5.75" x 3.75" (14.5 x 9.5cm) aperture.
This particular frame was a cheap one from Wilkinsons or Factory Shop I think and the mount came with it.
The good thing about framing these postcard size images is that you can easily change them if you get fed up with them or you change your decor.