I think they'll be aggressive myself. Dombrowski's style, and this is an all-in year. Rental players rarely cost a ton, even guys like Machado. Unless the other team picks up a ton of $ which the Phillies don't need them to do for the right guy.
The nice thing is the bullpen has stablized and may even be deep once everyone is back. Wouldn't rule out another piece there but a starting pitcher is more important.
An adequate CF or decent OF bat who can field, rather than a big swing, also perfectly doable. They just probably won't go after a 3B, SS or 2B, especially if Segura's timetable is moved up. Of course that and Harper coming back would be huge if the team is still right where it is now on September 1.