This note is not rare, at least here in Norway. They were produced in London by the Goverment in exile and there were two series, 1942 and 1944. The 1 and 2 kroner from 1942 and 5, 10, 50 and 100 kroner 1944 were released for circulation in may 1945 and withdrawn a few months later. 5, 10, 50, 100, 500 and 1000 kroner from the 1942 series were not released for circulation, but a few sets from 1942 were presented as gifts to prominent people after the second world war and I believe seven sets are known (and a circulated 50kr 1942 was discovered on ebay.co.uk last year...nobody knows how it found its way into circulation). There are also several specimen notes known.