For those who may be interested, I came across online this quite exquisite pickelhaube that was offered for sale on Sotheby's Auctions closing in December. It was described as the personal helmet of Duke Carlo III of the Duchy of Parma in Italy. To my knowledge Parma was the only Italian state to adopt the pickelhaube for its armed forces, although a variant of the pickelhaube with a thin spike and ball on top was used by the civic guards of the Papal States and Tuscany, among others. Not sure of the ultimate hammer price, but along with the accompanying epaulets, it was estimated to go for between $30,000 and $50,000.