This chart/map from Norway's South Coast features the Head of Oslo Fjord. It also still has a card showing changes to the chart from 1975.
As shown in images, this chart shows some age-marks, small tears and yellowing.
It would make a gorgeous piece to frame and hang on the wall. Perhaps you've sailed these waters?
Old charts are hard to come by as once out of production retailers are required to return stock to be replaced with new editions.
Measures approx: 104cm x 70cm