It's surprising how elusive many of the Norwegian 1K pieces are in Unc. I made the mistake of passing up a nice unlisted official looking 1958 mint set back in the '80's because the owner wanted $55 for it. The first listed set is a 1960 with a mintage of "200". Back in the '80's you could buy stacks of rare moderns for $55 if you could find them. I picked up a spectacular Gem 1954 Indian PR set instead for $3. It was hard to find rare coins (always has been) and you couldn't be sure something was rare because everything listed for a couple dollars. But $55 went a very long way if you didn't spend it all in one place. Oh well. I passed up a lot of even better deals than this one.
The Proof set I bought instead lists for over $2000 today but experience tells me the Gem '58 Krone is 20 times scarcer.