The Harpeleik is also Swedish. Although the markings - if there are any - show major chords, there's nothing stopping it being tuned to minors. The arpeggio of pegs for each chord lets you play the melody - so not sooooo simple. Try http://www.musikzentrum.de/hopf/default.htm for all sorts of Zithers from a current manufacturer (but not the Alpine Zither - that's the one with a fretboard and five strings on it: Third Man theme, etc.). Hopf are also very helpful for getting new strings.
TomB