My dear aunt's nickname was Justie (with a long "u" as in "duty").
Reportedly Hungarian, but from the time of the Austro-Hungarian empire, I'm wondering if Justie was a name likely to be popular in Budapest, Vienna or perhaps Galicia. We know little about my mother, her sister and their background. This name just doesn't come up on this website, except as Justine...with the "u" short as in "lusty" though maybe the French heroine Justine
was pronounced with the long "u", accent on the 2nd syllable.