I can see why you're having trouble finding a native mix - as usual, companies that sell "native wildflowers" for Georgia also include non-native species like Four O'Clock and cosmos. I found the following site that will give you what you want, I think, although it only sells the mixes by the acre, which could be a problem unless your driveway is quite long or you make the wildflower area rather wide.
The organization Pheasants Forever has a site that sells specialty mixes for any state in the US; it has several Georgia-specific mixes, for example:
Mid South Understory (for part-shade)
Big Bluestem (Kaw), Partridge Pea, Lanceleaf Coreopsis, Plains Coreopsis, Illinois Bundleflower, Purple Coneflower, Virginia Wildrye, False Sunflower, Wild Bergamot, Switchgrass (Blackwell), Foxglove Beardtongue, Black-eyed Susan, Brown-eyed Susan, Little Bluestem (Aldous) and Indiangrass (Cheyenne).
GA Basic Upland Habitat (possibly better for northern Georgia)
Autumn Bentgrass, Black-eyed Susan, Evening primrose, Little Bluestem, Lemon Mint, Indiangrass (Cheyenne), Deer Tongue Grass, Lanceleaf Coreopsis, Big Bluestem (Bonilla), Wild Bergamot, Indian blanket, Brown-eyed Susan, Grayheaded Coneflower, Partridge Pea, Stiff Goldenrod, Purple Coneflower, False Sunflower, Dotted Mint, Purple Top
There are other mixes as well that might meet better your needs. The site is here.
As with any wildflower garden, weeds will infiltrate or sprout from dormant seed in the soil, so you'll need a plan for handling those that doesn't involve burning, since the garden is right next to the drive. I would recommend an organic mulch after the seeds sprout (maybe wait until the following year to allow plenty of time for the new seedlings to appear), renewed annually. You'll have to hand-pull or spot-spray any weeds that appear during the first year.