The cost is dependent on your choice of components. It's not on .300 WM, but the following are the semi-custom budget builds I did using Savage LAs.
View attachment 542082
.257 WBY:
As pictured...
Savage 110 LA = $300
Oryx chassis = $400
McGowen prefit = $432
MBM 4-port = $125
Custom bolt handle = $90
Recoil lug = $30
Barrel nut = $30
5-round PMag = $40
$1447
View attachment 542084
.264 WM
Savage 111F LA with factory trigger adjusted down to 2.5 LBS, pre-fit 26" SS X-caliber 5R, 1:7", Choate sniper rifle stock, 4-port beast brake, Burris XTR sig rings, 20 MOA Weaver rail, and topped with Leupold LRP 6.5-20x50 FFP.
I do not remember the component price breakdown, but it was ~$1K.
View attachment 542085
.270 AI (
https://www.longrangehunting.com/threads/my-budget-270-ai.97745/#post-691221)
$199 - Savage 110 L/A
$370 - Lilja 30" barrel, 3-groove, 1:8, #6 contour (.750" at the muzzle).
$250 - square action, thread, chamber, crown, sand blast, and install (by Dave
Young, Sand Coulee, MT)
$110 - B&C Duramaxx stock (olive web)
$ 40 - EGW zero MOA rail (might have to go for a 20 MOA later)
$ 30 - lug