yep. quality barrels don't come cheaper than $250. for what you're looking for, you might manage $300 but shipping will push you over the limit.
I did similar with my Savage 11. I dunno about Rem 700's, with Savage it's easy to swap barrels. I could take it to a gunsmith but it really isn't anything to smith... it's like you don't need a mechanic to rotate tires on your car. If you got the tools then you're set. need action vise (you can make one) barrel wrench (you can make one or buy one) and a no-go, go, and field head space gage. you tube & forums provide plenty of help, and instructions. just loosen existing barrel, remove, install new barrel, head space and tighten. then test with the go & no-go to confirm you've done it right.
I did that and cut $175 off gunsmithing fees.
swapping stocks is easy too. I just bought a ready-to-go one from Boyd's. they make good stocks, and it's only about $120 shipped. most are with a bull barrel channel and will allow the barrel to free-float, if not you can ask them to widen the channel on yours or you can inlet it yourself.
when buying the barrel you need to your what twist you want, I'm not familiar with 30 cal twists so you'll need to find out for yourself. use the miller formula. http://accurateshooter.net/Blog/millerformula.xls
the longer the bullet the aster your twist.
if you have the tools you can always do it yourself... the barrel i mean. buy a blank with the twist you want, just profile, chamber, thread (or profile to work with 700 receiver) and crown it yourself using a lathe. blanks are cheap. like sub-$100 cheap. but you need the tools, which are not cheap.