Ah man. I can't find the S.Drives on the Yokohama website, either. They're still available on Amazon, but that may be remaining stock. According to the Yokohama website, you can get the Neova AD08R in most typical sizes for staggered 17/17 and double staggered 17/18 on these cars;
I never hear about these, but they are an extreme performance Yokohama tire after all.
As for Nankang, they actually aren't that much of an obscure brand. They've been around for a long time, but they aren't up there with Yokohama, Michelin, Toyo, Bridgestone, etc. in terms of quality/performance/reputation. I'm currently running their NS-25 All-season tires, and they're honestly fine. They're not impressive, they're not dangerous, they just get the job done in a wide range of temperatures and weather conditions. I can still corner pretty hard in my car, but I understand the limits of tires like these. And unlike some angry internet reviewers, I understand that you don't attempt "performance driving" through turns in the rain on budget friendly tires... in a lightweight sports car. So it can be a viable option, but even I don't want to see all the good summer performance options disappear for these cars. I don't want to stay on "honestly fine" tires forever.