I'd say 'timeless' rather than 'dated', and I've always been puzzled as to why it didn't enjoy any sort of popularity surge when
Justin went so viral.
Usually I don't enjoy -ine or -een names, exceptions being those, like
Caroline, that are pronounced -ien. But
Justine is a name I've always loved for its stylish dignity as much as for its meaning. I would seriously consider using it.