165gr SBT.
I can pick up a new powder if what's on hand will not work.
This one it is:
https://www.sierrabullets.com/store/product.cfm/sn/2145/308-dia-165-gr-SBT
Your powders are more adequate for 223 and small rifles. 300WSM is a large margnum rifle (pretty much the smallest LM, but still a large magnum), so you might find some loads, but accuracy will be more or less great. 4320 is an especially old powder, I'm not sure it is still commercially available.
Anyway, you can check Hodgdon't for loads:
http://www.hodgdonreloading.com/data/rifle
Use datas for Nosler partition. Start at min load. There's a load in there using varget, but varget is at the end of its capacity, so it might not produce the best load. If you want to stock up on a single powder that will do pretty much anything 300WSM, try to find Win760 or H414 (they're the same powder).
This is what Lyman 48th edition says (Note that XMR-4350 is not the same as IMR4350 nor the same as H4350):
165 gr. Jacketed Ballistic Tip
2.850" OAL
BC: .475
SD: .248
Powder, Sugg Starring Grains, Velocity (fps), Pressure(P.S.I.), Max Load Grains, Velocity (fps), Pressure (P.S.I.)
760 59.0 2812 49,800 65.5 3067 61,400
H414 58.0 2822 51,700 64.7 3045 60,800
IMR4350 59.0 2684 44,200 65.5 3049 62,500
XMR-4350 60.0 2730 44,500 66.5 3053 60,900
N160 61.5 2785 47,800 68.2 3073 61,600
RX19 62.0 2688 43,800 68.5 3046 60,900
IMR4831 62.0 2688 45,000 68.7 3016 61,200
WXR 63.0 2740 45,800 70.0+ 3055 61,600
H4831 65.0 2775 49,700 72.0+ 3024 62,400
Magpro 71.0 2821 44,100 79.0+ 3103 55,800
