You don't need to spend that much, especially if you DIY the install. I installed a cheap Linux based head unit (ATOTO F7 WE) in my wife's old commuter car last weekend. $180 Canadian for the head unit, $25 for an aftermarket wiring harness adapter. Took a few hours to splice the harness together and install the head unit in the dash.

The head unit's software is definitely a little janky, but it doesn't really matter as all she uses it for is CarPlay anyway. It even supports wireless CarPlay so she doesn't need to take her phone out of her work bag - our brand new Kia with an expensive infotainment system doesn't even support wireless.