Rear end sag

I have a 98 Astro Van-extended AWD. It alwayslooks like the rear end is drooping a bit. Anyone else notice this problem? I also need new rear shocks. What is available-looking for high end shocks. What's out there?
Thanks.
Bob

Have the chassis ride height checked, front and rear. If it's low, it will require spring replacement to correct it. Springs determine ride height, shock absorbers do exactly that, they slow down the action of the springs, they DO NOT affect ride height.