Other then the cheap Craspco and Redfield(redfielddoes make ok stuff also.)weaver style stuff, your gunsmith is correct. Goto Leupold.com and see their different styles of bases. Burris, Warner, Weaver will work fine it just depends on what look you like. I prefer the Leupold or Burris Dual dovetail or double dovetail bases and rings. The STD Leupold ringsand baseswith one turn in ring and one windage adjustable ring are prob the most popular.