JDG already answered you. Get a 0 MOA rail. The 10 MOA, 20 MOA or 40 MOA are for extreme distance shooting 1,000 yards/meters +. You intend to shoot at closer range, and so you need 0 off-set in your rail. Regarding specific manufacturer, I use Ken Ferrell rails on my bolt actions. If you can, purchase the G-Force rail for added stability.
Geno