We own three strikers who are 30 or close to being 30. This summer will probably be the last time to get solid cash for Vucinic, Quag and Matri. It's hard to expect all three to be sold, but I'd do my best in Marotta's place to sell all of them. It will be especially tough to find a buyer for Mirko, due to his wages (3.5m iirc). But if Vucinic and Juve leave their mark in CL knockouts and attract attention, then selling the trio of strikers is doable. These three won't get any better than they are. Quite the opposite. If there is time to sell them, it's this summer. Their sales will easily finance a top striker. Adding Giovinco and Llorente and the cash we will have left, we could create a sweet and young attacking base (top striker, Seba, Llorente, 4th striker).
But this will require some monster job from Marotta. Won't be easy at all to buy a top striker and sell three of your own strikers, especially if we have in mind their age and their not so good reputation as the weak part of an excellent Juve team.