The coins as advertised as geniune are counterfeits. The pieces coming out of China, Hong Kong, Korea, Singapore are almost all struck from counterfeit dies. The Chinese government doesn't block these people from producing, marketing, selling, or delivering these goods. The Chinese people are like the Ferengi of Star Trek -- Rule of Acquisition #1; Once you have their money, you never give it back.
I guanantee that if you send in money, the items will be shipped to you. What you will get are silver or gold plated items of nominal scrap metal value. Sometimes they aren't even silver plated. But you'll be left with no way at all to get your money back. That's because the entire amount of the sale is factored into the inflated "shipping" fee. It costs about $10 to send those fake Pandas from China to you.
Popular pieces to be counterfeited are any Gold or Silver Pandas. Any crown sized coins of China, Japan, Korea, etc. Also, expensive rare Japanese provincial coins of Edo are commonly encountered.