Looks interesting, $15 shipped: https://www.ebay.com/itm/Makeblock-Robot-Gripper-Makeblock-Arduino-PI-Compatible-Open-Source/224127314778
Claw opens to 3". Seller warns it's PVC, not aluminum. Appears to have a simple DC motor & leadscrew. Nice looking IMO, I'll probably get one, 22 available. $12.72 for 3+ units!
$30 at https://www.studica.com/us/en/Makeblock/robot-gripper-black/86502.html, which has better pictures.