If I might offer some advice....
Don’t buy a 338, yet...
Your post sounds a lot like mine about seven years ago. I got the bug so bad I ended up starting my own rifle company in 2017. Coincidentally, I was between a 98 bravo and a Sako TRG 42. I went with the Barrett because I got a great price on a pmII as part of deal, and that it was American made.
At the time, I got a lot of advice from the forum not to do it, too much recoil, you’re not ready, as well as lots of folks trashing Barrett, to which I politely replied by telling them all to get bent lol. Ultimately, I’d recommend you doing whatever floats your boat. I would posit though that for a time you might have more fun out of something a little less serious. I’ve had three 338 lapuas, and I’ve all but abandoned shooting the caliber, even though I have thousands invested just in reloading components.
For a magnum, I’d look hard at 300 PRC. You really have to go to a 338 Improved to have any significant ballistic advantage over the PRC. I’m likely to re-chamber mine in Ackley sooner or later. Also, you can get match grade ammo from Hornady for about the price of Lapua brass in 338. Matches are the most fun I think you can have with a rifle and I don’t know if a 338 Lapua would be welcome at many.
If I could do it over, I’d probably start with a 6 Creedmoor or perhaps a 6.5 (little cheaper factory ammo). There are good factory offerings from Bergara and Tikka as well as Sako. A custom rifle from a reputable builder is always a joy to own. Spend the money on good glass. You’ll need many peripherals as well (chrono, rangefinder, shooting bags, bipod, etc).
Shoot me a PM if you’d like to chat. Maybe I can pass along some of the experiences I’ve had. Best of luck to you regardless. It’s a great sport.
Shep