The problem was solved in the end with some fairly generic images from google: HSTs, Sealink ferries and the like. The next issue was getting (read guessing) the appropriate size for these on the screen before printing. In the end I filled half a page of different sizes and then picked the most logical to scalpel out. These were mounted on oversized 20 thou plastic with a Pritt stick, framed with 20 x 10 thou strip and trimmed. A little UHU fixed them to the back wall.
If you've enjoyed this rambling rubbish, show the love and splash out on an Americano for a starving muso. https://www.buymeacoffee.com/chrisford2Q