Re: Stevens 200 Action / Budget Long Range Rifle Build
The tools you'll need are a nut wrench (Stainless, $25 from Jim Briggs) and an action wrench. The cheap wheeler one from Midway works good.
For the rifle, you'll need a magnum bolthead. You can get a bare one and all the parts from midway.
Get your prefit barrel from any of the manufacturers. A Shilen from Jim Briggs would be a good choice. Or, one from Sin Arms fitted with a muzzle brake.
You'll also want to upgrade stocks. I'd look at Stockade, Bell & Carlson, and Choate.
You could also get a better trigger. I've had very good luck with a factory 3-screw. You could also get a Sharp Shooter Supply or Rifle Basix SAV-2.
The tools, bolthead, and barrel are the minimum to get you shooting. The stock and trigger will bring it up to a great rifle.