Twinglet..i was wrong Austrian Bersaglieri were'nt called "Cacciatori Esteri" which in fact were composed mainly by Suiss volunteers...As you probably know the "Bersaglieri Austriaci" that fought quite well at Castelfidardo were formed by undercover "volunteers" sent by Austro-Hungarian Empire to defend the Papacy..they managed to recruit personel to form no less than five Btgs..
From the Official History of the Marche/Castelfidardo Campaign published by the Italian Army HQ during the Twenties of which i have a very rare and expensive copy full of maps and plates i read that "the coat was black with white metal buttons, turquoise baggy type trousers, green épaulettes with yellow neck, képi (no mention of the colour) with yellow piping and green plume"..it's interesting that the tunics were black instead of blue..a more recent source (L'Esercito Pontificio da Castelfidardo a Porta Pia - Milano, 1976) , the author , Crociani, said that he was unable to find, even in Austrian Archives, any info on the appearance of this unit (remenber they did a sort of clandestine operations in Italy ) so he had the only choice of reporting the old "Italian Official History Source " (La campagna delle Marche e dell' Umbria - by Gen Attilio Vigevano - Rome 1923) but he thinks that the black of the tunic was, in fact, a dark blue...personally i have some doubts about that because all other descriptions of uniforms of the other Pontifical units , including plates, by Gen Vigevano .specify "blue" (for example line infantry, cacciatori ecc..) so the authour was absolutly capable of distinguishing between blue and black...anyway the tunics of my 28mm minis of that unit will be, for the sake of variety, "black". included is a pict of the only plate i find of this unit ..(Official History by Gen. Vigevano)