Well, I agree with both WN2 & NR to a certain point. There are incredible quality watches coming out of China, including tourbillions. However, the biggest problem is that many so called tourbillions are just open heart watches that the resellers label as such. There are also legitimate tourbillions that can occasionally sell for that little on eBay but that is rare.
Go over to Watchuseek.com, check the Chinese Mechanical Watch forum, someone may know what movement that watch uses, if it is legitimate.