$750 to $1500 is the minimum I would recomend for a scope. High end optics start at $3k and go to 5k and beyond!
For .308 at 300 yards or less, you are in great shape at that budget. Your priorities should be:
1. Glass quality: the most important, enduring quality. What good is magnification if you cant make out the detail. A big blur isnt more helpful than a small blur.

2. Reticle: for shooting at random unknown distances, a mildot based reticle is essential. (Tactical/prs style) For known distances a BDC reticle will suffice. A great choice are the christmas tree style reticles like vortex EBR that let you aim and adjust follow up shots for windage and elevation without dialing in. (Most underated innovation in optics and is more important than quality turrets.)
3. Focal plane: for reticle ranging at unknown distances you will want a first fcal plane scope. If you are shooting at a range with known fixed distances, you may prefer second focal plane optics where the reticle stays tiny even at high magnification.
4. Magnification: at 300 yrds or less 10x or 20x is appropriate. Skilled shooters can beat you with a fixed 3x, but high magnification will help make movement of your handling more apparent and is a good training aid.
3. Turrets: at 300 yrd or less, wind is not a factor and dialing elevation is not necessary with a mildot reticle. I love good quality turrets, and shoot mostly on a S&B PMII. It is a tactile experience that I deeply enjoy, but is not strictly needed. If you get turrets they must be high quality and repeatable.