I can find no record of Giacinto Melillo ever making silver spoons !! There are none to be found so no way to determine value without something to compare !! And since they are not marked for purity with either 800 or 925 which is the Italian standard for silver,,cant even guess at melt value !! I would suggest you go to a jeweler and have them tested for content !! As far as him being the maker of the spoons I have no idea !! Many times there are things produced in a studio that the artist himself never touched !! His design but made by others !! That also affects the value !!
How did the wing get broken ?? 2nd pic ?? That is going to affect value !!