I'm looking for a set of Burris Signature Dual-Dovetail 30 mm High Rings, #420584. These have been discontinued but hopefully someone has a set laying around. If I can't find those I'll settle for a set of Burris 30mm Signature Standard Rings Matte High #420581. These are the rings with plastic inserts to auto-align and protect the scope body. Who can help me out?