I am in the process of a Stevens build. It was a .270 now holding a CBI .260 rem barrel. Having prior issues with two piece bases I went with a one piece picatinny base. It's a Weaver and it cost $40. I then went with the Burris XTR rings. The simplicity and the fact that everything is tight and won't loosen up even if I remove scope is why I went with the one piece base. EGW also makes reasonably priced bases.