I do not think you would have a problem selling those bucks. As far as a management issue, you need to start shooting some of your deer before things get out of hand. 70 deer on 650 acres is way to many. I hunt on 7500 acres and we have around 350 deer with a buck to doe ratio at 1:1.5. You should probably sell those buck and throw in a few does along with them. People will pay to hunt, especially if they can kill multiple animals. I would get some advice from a biologist on what your numbers should be and then let your heard grow.