Chances are it's a scam. Every "real" site on the web has them for 4k-6k. A one off deal for 1250 sounds scammy.
I know how you feel right now....excited to mine! Q1 is right around the corner and new machines will undoubtedly be released.
When this happens the price gouging will slowly go down on the S9. I also eagerly await machines that are ready for release.

I have already contacted sellers on alibaba few weeks ago. 2 things you ought to know:

1. Many sellers there arent trustworthy. Too many scam cases.
2. Even if they are not scammers, the price are not updated. They will quote you usd$4000 there-about for an S9, instead of the advertised price of less than usd$2k.

Hope this helps.