Those are load lever shocks that are normally put on a station wagon or a light truck to help support the weight of a heavy but temporary load. They are not coil over shocks that have a threaded body to adjust ride height. Those shocks as well as a coil over requires the shock mounts to be reinforced to sustain the weight of the car. The good part is that both ends of the shocks are mounted to the frame and axle with relatively strong brackets as opposed to bolting to the trunk floor as found on a Camaro or Nova car.
Yes but don't be surprised if the car settles a little more as those springs are providing lift.
They were common back in the seventies when car fashion dictated a rear high stink bug stance as opposed to a low rider stance to be cool. Just like with clothes what is in style changes regularly over time. Hang around long enough and you can see the cycle repeat.