You can check out some existing builds here [0]. And you can also save/post a public link here to your custom build, once you have a tentative one.
My price range is around 1K, but wow there is plenty of choices, look: https://pcpartpicker.com/products/video-card/#sort=-price&pa...
My base workstation is a Dell T5800 series and it has a 2x Gen 3 PCIe x16, do you think it would need more upgrades? like power supply? It has a Dual Xeon E5 and all memory banks are full at 256GB of sweet RAM :)