That budget seems light to me for a render station and animation, i can't see you being able to get the right CPU , RAM and Graphics card in that price bracket. I am not saying you can't build a good PC for that budget but maybe not a workhorse workstation, you could blow that budget on the GPU alone although i can say that the Quadro K2000 is a really good option for a low budget.

Really you will need a min of 8GB of Ram too so you are looking at

$500 for the Processor
$425 for the Quadro K2000 card
$75 approx for 8GB RAM
$300 approx for a good MB

That's $1300 right there and still no Case, Power supply, CPU fan/Cooler and Optical Drive.
My latest build cost me just over $ 4000 so you can see why i am skeptical.