For that budget you might as well get quality. BCM, Daniel Defense are w/i your price range and offer a great value and no guess work (will it be a lemon?). Since you have the money there's no reason to settle.
I have read your other post. I always recommend purchasing a complete upper and lower separately so BCM suspending complete rifles isn't such a big deal. In fact it's encouraging. Maybe some of the normal DPMS customers are recognizing true value and quality finally.
Do either DD or BCM offer 1 in 9 non-chrome lined barrels in their rifles or uppers? That would seem to be the best choice for a dedicated varmint rifle to get the best accuracy with light weight varmint bullets.