I've heard Love County has quite a few. Anywhere along the Red River would be loaded as well. I have seen them hit on the side of the road coming into Hinton which is pretty close to Fort Cobb. They are even at Black Kettle WMA along the river.
I've never hunted public for them but I am told that all these have good populations. I am thinking about heading to All About You ranch in June. Hopefully they will be around the water holes.