Look into Leavenworth County in Kansas. Seems to meet most of your criteria especially, price per acre, homeschooling, vaccinations, and type of land (wooded, pasture/prairie).
Also, the county does not have building codes outside of any townships.
We just bought 7 acres right on the county line next to Douglas county and 10 mins outside of Lawrence KS.
There are a lot of homeschoolers and homesteaders around here. We have a 4 and 6 year old that go to the Waldorf school here.
Let me know if you have more questions.