I can tell you, without a shadow of a doubt, that the aircraft depicted is supposed to be a Bristol Britannia 313 Series. The main identifying feature is the engines with subtle turbo-jet exhaust pipes indicated.
In 1955 El Al had ordered 3 of these Britannias, only to increase that to 4 by 1957. El Al did engage in an enormous amount of publicity to promote their new aircraft/routes, and this sort of item was typical -- probably
primarily used in airport offices, waiting areas, and reservation counters as well as at travel agent offices.
As far as the rest of it is concerned, I'm sorry, I have no info.