If its for a Remington M700 action, Brownell's lists 4 different ones priced from about $75 up to about $135, depending on the manufacturer. The Badger Ordnance is probably the best of the bunch for $130-133, depending on the length of the action. You may also go to www.snipercountry.com and check the emporium. Sometimes people post them for sale there. Good Luck!
I just put a set of those Burris rings on my 416wby, got the optional .020" insert set and used the +.020" in the rear and the -.020" in the front and ended up with .040" tapor total. Worked perfectly. The extra inserts were another $10.00 but worth it for the additional adjustment.