What is the cost of a small RV site

I don't believe you can park an rv at the park. There are a few close by though that you can find by googling

You can certainly take a small RV or van into the campground at MVNP. Big rigs, probably not. No hookups, check the NP website for prices

We where there a few weeks ago and the only accommodation we saw for RVs was a parking area to drop a 5th wheel or pull behind trailer so you can drive up and back. There was some tent camping open though.