Hi again TCW,
I still say the Browning A-Bolt Composite Stalker is your gun. (previous link in last post I gave you)
However, one more rifle I would check out for sure is the Howa Lightning. Available in .308 and meets your price. Here is a link for you.
Howa Rifles
One other thing. I don't know what your intent is at 500 yards, ie. paper targets, hunting, etc., but, if you're needing a caliber that will provide effective downing of medium size game for example, I would look into a cartridge that carries more energy out to 500 yards. I would use a .308 out to 300 yards for this and have no concern but, it drops off a great amount those last 200 yards.
Lets say you want to have at least 1250 ft.lb of energy at 500 yards to be effective without having to place an extremely accurate head shot. A .308 is going to give you an average of 800 to 1200 ft.lbs.
Additionaly, todays bullets may require a faster speed at which to fully expand the bullet. A .308 traveling at 1200 to 2000 fps at 500 yards may not have enough velocity to ensure proper bullet expansion.
If you expect to be using your rifle for this, I would move to a magnum caliber rifle. A 7mm WSM - 7mm Rem SAUM or .300 WSM would be good choices. These are still short action calibers as is the .308! Another benefit is, magnum calibers have a much flatter trajectory out to 500yds!
Food for thought for you. Good luck on your first bolt action rifle!
Marshall