Schiit Saga which tubes to order?

In my Line Magnetic 508, Amperex(Bugle Boy) blew up Tungsol( American made NOS) with more refined sound all around.

https://www.ebay.com/itm/PAIR-OF-6SN7GTB-AMPEREX-TUBES-NEW-6SN7-NOS-NIB-Vacuum-Tubes-Bugle-Boy/26392...

I should clarify.. a Russian 6N8S (NOS) is the stock tube for $349.00. The Tung-Sol 6SN7 is available at $374.00 and both the Tung-Sol 6SN7 and the LISST is available for $414.00.

First question; who is selling these tubes and quoting the prices? Only buy from reputable dealers.

So, I assume you are looking to buy NOS tubes rather than new production. There are so many brands and variations. There are different variants of Tung-Sol, you need to know which version you are buying. One TS oval plate will cost over $300, it's a rare tube from the 1940s and one of the greatest tubes of all time. There are also NOS TS tubes for $50 each.

http://www.schiit.com/about/news/octal-lisst-new-tube-options
Why buy a LISST tube? Then your preamp would be all solid state.