This, is an "easy" one and I already may have the rifle(s) to offer as my solution to the OP's query.

I bought my first P-64, an unfired Alaskan-.338WM 47 years ago, almost to the day, aged 21 and a working "mountainman" for the old BC Forest Service-this included solo stints of three months, NO breaks, on remote fire lookouts in Grizzly country where the "B machine" helos we used had strict weight limits and ONE rifle was IT.

During the intervening years, I have owned 43 P-64s and two custom Classic sts rifles plus about 100 other big game rifles and I STILL consider the P-64s to be among the BEST serious hunting/working rifles ever made.

For ME, you may well differ, I would choose TWO to meet this specification.

1. .338WM Alaskan, good synthetic stock, Leupy 1.75x6 MHD and M-8 4x MHD, in Talley QD screwlocks, Brockman rear peep/base and a "Sourdough" front sight. Load ONE bullet weight, using different types if you are "techy" or just shoot 250NPs over RE-22 to make 2800 at the muzzle and with sub-moa accuracy.

I have four VERY clean specimens of this rifle and seldom use them now as I carry my Dakota .338s, a pair, for most hunts. I like the 23" tubes as I am a short guy and BC is kinda bushy.

2. Fwt.-270Win. all changes as above and scopes are Swaro Z3-3x9, or, Leupy VX3-2.5x8 or Conquest 3x9s. I shoot 150 NPs over RE-22 for hunting and whatever 150s for practice as I do 250 whatevers in the .338s for the same purpose.

I have changed the trigger guards to factory steel ones, retained the alloy floorplates and tuned the triggers on all my rifles.

I have two originals of these and a "made up" one on a 1946 std. action using a Classic sts FWT. tube and a modded Micky MK-X Edge stock, now my alltime favourite .270.

IF, I were younger, I would have Ed Lapour's flanged safetys installed on all of my dozen P-64s and Darcy Echol's 4+1 mags. on the .338s, plus have the Classic gas blocks installed on all 12 of my remaining P-64s.

All of my 10 originals, most are 95% at least are rigged this way, but, I no longer shoot most of them, however, the above .338/270 combo is my concept of the "best" in P-64s for hunting as the OP describes.

All of THAT said, my ideal setup would be a .270 on a "roundbolt" Brno 21H action and a 4+1 .338 on a Brno ZG-47 as these actions are the pinnacle of production sporting rifle actions and even better with minor mods.