Had to improvise witb excellent! results. Can't find that Amer Picon so I used Bigallet China-China Amer and for the vermouth, 15ml Cocchi Dopo Teatro Vermouth Amaro and 7.5ml Dolin Dry. Definitely making this again.
I haven't had Bigallet, but perhaps Amaro Ramazzotti is available in your area. I suggest it because Ramazzotti is the basis for a recipe to make 'old' Amer Picon. I don't have a local source for contemporary Amer Picon either.