For some of the best glass and coatings, it's hard to top Swaro for hunting. They have the BRX and BRT reticles that are mil-based and have a kind of Christmas tree shape for elevation and wind holds. Some great demo pricing here:
Swarovski - Camera Land NY
If you have a go-to load you will be primarily using, you could do a Leupold VX3 with CDS dial made to your load's specs and atmospherics. Not as accurate as dialing in mils or moa, but fast and probably plenty accurate out to 600 yards for big game.
For exposed turrets and more 'tactical' setup, I like the SS 3-15x42 FFP from SWFA in that price range. There is a thread on here about zero stops available for them through a member here.
Another great scope worth mentioning is the Bushnell elite 3-12x44 with G2 reticle. Lots of happy users out there. I've been lusting after the new Gap-spec'd LRHS 3-12x coming out soon, looks to be the ultimate long range hunting scope.
There are the Vortex PST's too that are great for the money and have zero stop and illumination, but on a 300 Rum the SS may be a little more robust and shed hard recoil a little better, especially if braked.
Good reports of the Weaver Tactical 3-15x50 as well.
Some food for thought.