LR3:
What type of shooting is your friend interested in doing?
I looked at Western Precision's website and found no rifle specs. Appears the site is fairly new.
.5 MOA at 1000 yards (roughly 5") is very good shooting - better than most benchrest match winners will shoot on anywhere near a regular basis. [See the Williamsport range results -
The Original Pennsylvania 1000 Yard Benchrest Club, Inc. The Birthplace of Long Range Shooting.] A 338 LM is almost never seen at a benchrest match since the various 6mm benchrest cartridges rule there. Bottom line, "your results may vary."
LRH had a great write up on the 338 NM at
338 Norma Review
Also see
http://elr-resources.com/Sniper%20Pro%20.338%20NORMA.pdf
BTW, HSM/IQ Metals also offers 338 NM ammo - see
HSM 338 Norma 300gr Sierra Match King
And as far as component costs, I just did a search on
In stock ammo, guns, magazines, and reloading supplies and found no instance where Lapua brand (or any other brand) 338 LM brass is less expensive than Norma 338 NM brass. Otherwise costs are identical. Is Lapua preferred? Yes. Is Norma good? Yes. [BTW, Jamison/Captech also offer 338 NM brass for less than Norma.]
Norma has done basically no marketing of 338 NM and its, IMHO, a case of chicken and the egg. Product not available yields low demand. Low demand yields low supply.
Last point...the reduced length of the 338 NM makes it usable with longer projectiles in mags where the same projectiles force single-shot-only with 338 LM.