For loading .308 Win, there are 4 powders that I simply can't live without: Number one performer for me (I shoot 168gr. - 175gr. long range bullets, and the occasional 155gr. Palma) is Alliant Reloder 15. Second would be Accurate 4064. For some reason, in my rifle, AA 4064 prints tighter, more consistent groups than IMR 4064 does, however IMR 4064 usually averages about 15-25 fps faster velocities- not enough to matter to me. Third choice is Hodgdon's Varget, and my fourth choice that I get outstanding groups with is VV N-140.
If those 3 are just not available anywhere, my secondary choices would be: Ramshot TAC (my number one powder for the Sierra 155 Palma HPBT, Hodgdon's BL-C(2), Winchester 760 (both BL-C(2) and 760 are outstanding powders, but a bit dirty for AR rifles), N-150, N-540 (both work great, but are overpriced and do not outperform N-140), IMR 3031 (good for lighter bullets), and IMR 4350 (everyone should keep a can of 4350 around, it works well in almost everything that uses a large rifle primer - and sometimes is the best choice).
I use nothing but CCI BR2 primers, unless I absolutely can't find them, in which case I use Federal GM Match.
I'm sure there are lots of other choices out there, but these are the powders that I personally have a lot of experience with in the .308 Win. My .308 rifles I load for are a Remington 700 26" heavy bbl (1/12" twist), Bell&Carlson A5 tactical stock, Jewell trigger (2.2#), Nikon Monarch 4-16x42 SF on an American Defense mount. The other is a custom AR10 I built, using an LMT upper and lower, PRS stock, Troy forearm, and a KAC barrel with a Trijicon Accupoint 5-20x50 on a Larue QD mount. The 700 likes the slower powders (RL15), and the AR likes the slightly faster powders (especially 4064) and ball powders (TAC, BL-C(2), 760) although I don't like cleaning up after them!