Shuguang 845B or Psvane 845 Hi-Fi series tubes

My amp is Mastersound 845. I've been using a pair of Shuguang 845B tubes. After 2 years (probably about 2000 hrs) one of them died. I don't see many Shuguang 845B on Ebay any more, they were quite good. There are some "new" constructions though ... Psvane 845 Hi-Fi series , about the same price as Shuguang 845B (note, these are not Psvane 845-T). How are the "new" Psvane 845 Hi-Fi in comparison to 845B?

I'm not sure how the "new" 845 tubes compare to the Shuguangs, but still has 845Bs if you decide to stick with those. They probably aren't as inexpensive as you found on ebay; however, as you metnion, they are getting tougher to find. I recently bought a spare pair of 845Cs because they are getting tough to find as well. Good luck!
I can't tell you much, but I can tell you that the Psvane 845-T tubes sound much better to me than the 845-B types in my own SET monoblocks. For the price they darn well should :-)
My understanding regarding the Shuguang 845s is that they make them in factory runs and then move on to another tube in the big tube family. Curiously the Psvanes were thought by many on certain other forums to be Shuguang products. I am sorry I can't comment on the sound quality but barring the KR etc. tubes you have little choice. I did see some very real looking NOS RCA 845s recently for $3 or 4K, but you can buy some decent amps for that and I thimk it was a running auction!
How about the Canada-Fuller 845GX. ? One year warranty, 15 day return policy if not fully satisfied from Hanshare-Electronics.
You may want to try the Elrog ER845 from Germany; they are suppose to be the cat's meow.