The newly-promoted Premier League outfit are planning to host the encounter at Selhurst Park on August 20.
"It is not 100% nailed down but it is looking positive," the South London Press quotes Parish as saying.
"I don't like calling things too early but as far as we're concerned it is done, we're just waiting for them to sign the contract.
"It came about just from people offering the game. It's a different world when you're in the Premier League, there is a lot more interest than before."
Palace secured a place in the top flight by defeating Watford in the playoff final at Wembley.