Vaccum Tube Questions

[GammaG]

Hello everyone, I am new here and have a question about a KT-88 tube that I was wanting to purchase. I did a little searching on some of the best sounding tubes for the KT-88's and found a tube called the Shuguang KT88-Z (KT88) Treasure Premium Quad Match for a price of around $357. Here is a link to the company that sells them: http://www.analogmetric.com/goods.php?id=1450 I already had a quad set of the Gold Lion Genalex KT88, but one of the tubes seems to be having some issues as I can't seem to bias them at the rated voltage that they require. So I figure it is time to seek a new set. I was also thinking on purchasing the (SED) Winged C's, but am not sure. My question is- Does anyone know if the Shuguang KT88-Z Treasure tubes are legit or a fake replica of some type? I just don't want to get taken. I was reading some of the fake reproduction tubes, and it really bothers me. Maybe someone here can direct me in the right path. Also, has anyone dealt with the website above?Thank You in advanced!!

John G.