If you think like that, I think it's impossible because china just banned bitcoin trading and not prohibits the sale of mining hardware, did you had taken legal steps because you send money through bank transfer, I think you have strong enough evidence to prove that they want trying to commit fraud as you allege but honestly I do not believe they do that.
You can find miners available in aliexpress and ebay china to buy the antminer series in these sites. When you exchange the bitcoin in fiat who limited amount via IMPS transfer you will never into any legal issues. Still bitmain delivery issue ongoing in the site. I noticed of the people created a thread about delivery issue for Bitmain direct purchases.