Old-Cat, you da' man. Bullet weight is the only constant once you squeeze the trigger. Not only heavy bullets, but heavy bullets that stay heavy bullets.
OP, choose your hunting bullet and pick up a couple boxes. It won't take many shots to get your rifle dialed in where you want for hunting season. Then have over a box and a half of rounds left to use many years in the future as your hunting round.
Buy the less expensive ammo and get your trigger time with that. You aren't worried about your point of impact with the practice rounds. Likely those won't impact exactly where hunting rounds do. Foucus on good shooting technique and you'll get lots of practice.
Since you are south of me down in Pueblo West, I can share from Colorado experience with Barnes X, TSX and TTSX Bullets over the last 28 years on pronghorn, muley's and elk. The Accubond and Partition are good as well as has been mentioned. I've loaded them for other family members, then join them over the animal for the field dressing and packing out.
Even at that, the .308 Win isn't a high velocity round relative to some other cartridges.
Traditional cup and core bullets from Remington, Federal, Winchester, Hornady, etc, are designed, per se, to perform very well within the velocity window of the .308 Win. and the 300 yard range you mention. Those aren't out of the realm for considering in my opinion if you want to steadfastly stick with one loading. Otherwise get a couple boxes for hunting of "premium" ammo and use a less expensive one for practice.
In any case I prefer controlled expansion bullets as mentioned for in the field. Particularly Barnes and more broadly monos in general. They harvest the animal cleanly, minimize wanton waste of bloodshot meat and there's are too many good memories and no bad memories to switch up to something different.