Earlier quoted context omitted.
Perhaps concerns about 'the over-militarization of police' is essentially a concern for situations where an extreme power imbalance exists between police and civilians, creating a much higher risk of totalitarian abuse and oppression by police in situations where the police force in question becomes corrupt or 'bad' in some way. (Disclaimer: I'm not making an anti-LEO argument; quite the contrary, I'm very pro-LEO, a…
Civilians can buy heavily armored vehicles, yes. They can also buy military vehicles, provided they are certified (like not carrying weapons) but it is definitely possible to be rolling around in a MRAP style machine completely legally.
Look up "The Big Sandy Shoot" on YouTube. All vehicles and artillery pieces you see there are privately owned.