I've spent at least thirty minutes cruising through the grass on Route 19, no Arbok. I've used at least two dozens of Honey when it finally wasn't raining on Route 14, no Ekans hordes. Just Bellsprout and Skorupi, every single time.
I tried GTS, but naturally people only want to trade them for Yveltal, Xerneas, Articuno, Zapdos, Moltres, or Feebas.
So anyone tips on how to get them? Or are they just really this rare and am I looking at a few days of mindlessly running through the grass?
You could also use the GTS. I put up a Shinx and asked for an Arbok. Ten minutes later, I had a Arbok. So far, Shinxes and Vulpixes have gotten me everything I asked for, except legendaries (didn't try).