Nvidia GTX 1060 3GB or 6GB are about your best option out of what is more readily available to put together a rig ASAP with all the same cards, at a resonable cost. BBT posted a video of the 6 card rig he built with the PNY GeForce GTX 1060 3GB XLR8 OC Edition

165+ GPU
1000+ MEM
~23.5mh ETH and ~268 SOL/s ZEC each @ ~60W per card.

https://www.youtube.com/watch?v=1uhSfOpvHks&feature=youtu.be&t=7295

Dag won't reach 3GB until early next year, so you should be good until then. The only problem with the 3GB cards you won't be able to dual mine effectivly.