I love my 845 amp, but I agree they do'nt tend to be cheap and you will be looking second hand. Some Italian names to consider, Mastersound, Unison Research and Viva. I have the Viva Solista and it is by a long margin, the best amp I have had in my system, but it is $10000 new. To get the parts quality, particular good large output transformers, which are critical to performance, costs money.
As to Chinese valves, as usual SuperTNT are having supply difficulties at the moment. Only the 845B is available now, but it is very good and reasonably priced