I have two sources for you
`Mostra delle Armi et Uniformi Napolitane 1734 - 1860` issued by the Museo Principe Gaetano Filangieri Napoli` of 1969 and `L`Esercito Borbonico dal 1789 al 1815`, Boeri-Crociani. Ufficio Storico-SME 1989`
I agree with you, hen`s teeth are more common.