Give a neighbor with a heavy disc a bottle of good sipping whiskey to come over and disc it for you.
Good heavy discs that'll actually do some work aren't cheap and aren't able to be pulled by an 8N.
I would look hard at that option, since the neighbor has 200 acres of beans, he more than likely did conventional tillage at some point. Farmers don't sell anything, they just let it return to the earth.
Craigslist probably isn't the place to find a small disc. Nobody wants them, therefore they don't have value, and it's not worth the hassle to sell them. ^^^ See previous statement about farmers letting old equipment return to the earth. I know you are the "Do it Yourself" type, SO if you really want a small disc. Find a coffee shop with farmers and ask. Someone will have an idea.
Next you'll be looking for a telephone pole to use as a drag, You'll have a whole yard full of farm implements, and there won't be any denying the "rancher" moniker then.
