The Forgotten Pistolero / Il pistolero dell’Ave Maria (Ferdinando Baldi, 1969)

This is the only film in which all three the most active “Old Men” in the genre appear: Franco Pesce, Franco Gulà - both with just under 30 SWs to their credit - and Eugenio Galadini a.k.a. Graham Sooty (12 films, 7 serious and 5 comedies).