If i were ferarri i would try to replace him with Button or Rosberg. Although if Perez can get his confidence back after his crash he is an option.
Neither of the first 2 mentioned will ever become a Ferrari driver. Perez will be, as he's part of the Ferrari driver academy, and therefore is being groomed to be a Ferrari driver
If he does crap today like he did in qualifying, I bet a blown diffuser that he'll be gone come Valencia.