Why not go for Giovanni Simeone?
From the established ones I would go for Firmino or Icardi.
I see many are saying that there is bad blood between Messi and Icardi, is this for real or just speculation?
LE: after looking at some highlights it seems that Giovanni Simeone, Lautaro Martinez and Maximiliano Gomez all share the same traits. Young south american combative strikers - similar to Suarez. In my opinion this is the type of player that would suit us. A striker that can bully opposition defenses, gets into space, combines well with teammates and has decent finishing.