Best Tubes on Market today?

I'd like to upgrade tubes on my Mastersound Compact 845 SET.
I'm getting a loud buzzing noise from both channels at  listening position which I find extremely annoying.
 My current tubes are Shuguang 845C (cheap Chinese electron). Pre amp tubes are Tungsram ECC82 and driver tubes 6SN7 EH. Probably all cheap stock tubes. I Love the the sweet sound but noise level is unacceptable.  Also very audible transformer noise, but I doubt there is a fix for that. Are there other ways to minimize tube/transformer noise?

What are the most reliable aforementioned tubes out there and what is the best place to get them?
Upscale audio seems to have quite a selection. PSVANE was also recommended by some. 
 I would prefer not to spend more than $600 on 845 tubes and hoping for reliable clean sounding tubes all around.    
I also have C2600 preamp with stock tubes. Any advice on those?