Tell Us Your Preferences...
Bull barrel, heavy barrel, standard, or lightweight contour?
16, 20 or 24"?
Stainless, chrome lined, or unlined steel?
Free floated barrel is generally better. Unlined chromoly is generally better and cheaper.
After we talked on the phone about a chrome lined barrel that still is reasonably accurate, I went online and looked at some 20" chrome lined National Match DCM barrels with freefloat handguards. Several manufacturers make them. Go do a search at Bushmaster, DPMS and other common manufacturers. There is a competition called DCM (Department of Civilian Marksmanship, I think) requiring a match rifle that looks like a standard issue military rifle, but it can be a match upper inside. See what you can find.
But I would branch out from that good Bushmaster and get a 24" stainless steel bull barrel, probably with 1/8 twist, and see if I can develop a deadly load with 69 grain varmint bullets. That would give you two very different rifles, just for fun. I have one with a Wilson barrel that keeps small groups longer down range because the heavier bullets get less wind buffeting.