Congrats! Your chambering is a very popular one for LRH for good reason.
I think your twist rate will definitely stabilize your listed bullets, and then some.
My first recommendation is look at investing in a reloading press (I like the Redding T7

you can set your dies, and never have to mess with them again), some Redding Competition Seater and Type S Bushing FL sizer dies. Once you have those two big things in hand, all the supporting equipment will seem like chump change and just show up on your reloading bench
For the price of loaded 338 Lapua ammo, I'm thinking you can get setup for reloading in 5-6 boxes of ammo.
Reloading will ensure you see the most of the precision potential of your new rifle, and give you flexibility to try different bullets depending on your intended hunting application.
Post up how it shoots!