Google Hart barrels, & they have current pricing, for length, taper, fluting (if any, & what style) etc etc.
Every smith is different but the one I had do my WSM build sent me a bill for $665 for a 30 cal Fluted #4 Hart 10 twist, a Centershot Rifles Mini Muzzle Brake, & sending my bolt out to get fluted in Idaho.
I'm sure his profit margine was small, but shipping to & from, & insurance etc was included.
He made his living as a gunsmith, so labor was his only real profit to be counted. I'm sure it was competitive as well. But any "mark up" on parts was minimal (single digits percentage wise).
Chambering & throating, crowning/muzzle brake, threading, squaring action & bolt, stock work & bottom metal etc. cost the $. Not so in much parts.
My best guess would be in the neighborhood of $3-350ish for my barrel, the way I wanted it.
Just noticed your an Oregon boy. Nice! Feel free to fling me a P.M. or a phone call Fri-Sun. I don't currently check in on LRH Mon-Thurs. too busy.