You're already provided with an owners manual I see. For anyone else looking for one, be sure to check subito and kijiji, loads off them on there. As mentioned Franco Luperini has pretty much anything, at a price though...
By the way, FCA have started reprinting them, though I much prefer an original example.
'66 Giulia Ti
'69 GT 1300 Junior
'03 156 GTA SW