What would be a fair price on a used/rebuilt motor/engine with labor? on 2005 Ford Five Hundred

The radiator had a crack in upper half from a deer strike and the engine over-heated while driving it to the mechanic. We are being told the motor needs replaced and I would like to have an idea of a fair price for this.

Asked by for the 2005 Ford Five Hundred
Engine assembly from Ford is about $4500, price about elsewhere but compare quality and warranty.About 15 hours labor to pull out engine transfer parts and reinstall engine.