Rental hitters, even impact ones, simply don't cost much in prospects. Think about what we got for Rizzo/KB/Baez, or what we gave up for Candelario. You can get impact talent a million miles from MLB or some safe/boring talent a lot closer. But talent and proximity are mutually exclusive. You should be thinking about deals headlined by someone like Will Sanders or Pedro Ramirez or Ronny Cruz.
There is more of a premium with pitchers at the deadline, but I'd still be a bit surprised if it rises to the level where a pure rental costs a Caissie or Alcantara unless the Padres become sellers. One of our top tier guys likely requires impact talent, additional team control, or a SP/RP package.