I have found this FLAK 30, probably the only one preserved in Italy, at the Museo Storico Militare delle "Alpi Giulie" in Tarvisio (UD) Cave del Predil.
You can find a full walkaround here:
http://cecetotoy.blogspot.it/p/flak-30-walkaround.html
http://cecetotoy.blogspot.it/p/flak-30-walkaround.html