Best Tubes on Market today?

If I was trying to solve a noise problem in my amp that I thought was coming from the tubes, I would not think for a minute that I should run out and spend hundreds/thousands of dollars on vintage tubes to solve the problem. I would first want to swap the tubes with another set of known "good" tubes just to see if that altered the problem in some way.

There is no reason not to buy a new set of tubes at reasonable prices to test this hypothesis. Upscale Audio and a number of other established sellers have plenty of quality tubes that will sound excellent and allow you to diagnose this issue without spending excessive amounts of money on a guess.
And I totally agree with all the posts that warn of buying tubes on ebay. That is nothing short of Russian roulette. That is NOT the place to go to solve this problem.

" I've been running 845 amps in my system for nearly 20 years, some noise is inherent to these amps "
I have a Line Magnetic 518iA 845 tube integrated, it makes zero noise

  I retubed my C2300 and MR-71 with NOS Telefunkun tubes. All tubes preceded 1970. I even bought one made in November, 1954. All NOS tubes made a great, audible difference in my system. And also quite a hole in my pocketbook!

ei001h- Far as, "best tubes on market"; the best are all NOS, from reputable dealers(as mentioned above). Since you asked about, "best’ for you; that depends on your taste in reproduction. It’s been my experience, that many like a warm, sweet, what some call, "tubey" sound. If that appeals to you, stick with British(ie: Mullard or Brimar) If a cleaner, more detailed presentation attracts you; go with German tubes(ie:Teles or Siemens). Somewhere in the middle, are Amperex/Bugle Boy, Pope and Phillips(Holland). NOS American tubes can go either way. The previous comments are focused on nine-pin Miniatures. I’ll include a list/comparison survey, which deals with the 6SN7 family. I’ve found the first author’s comments/impressions quite accurate (all my personal favorites are bottom-gettered) . With the prices that NOS output tubes are now commanding; current production is very attractive. No experience here, regarding SET output valves. http://www.dehavillandhifi.com/6sn7_vt.htm and: https://www.head-fi.org/threads/the-reference-6sn7-thread.117677/

hi
i would solve the noise issues by a tech and than replace both 12au7 at least. china is the worst source for any audio gear ide wait till i can afford it and go only with nos nib guaranteed (the older the better). i have experience with a few great nos 12au7 tubes these are my favourites :
1.mullard 10m goldpin 12au7 :the end of tube rolling,the cleanest tube with the widest stage and frequency extension the best audiophile grade preamp tube ever made in england has a fresh hint of brightness  .think if telefunkens had a soul...(if you even consider teles try amperex or simens they are sweeter sounding less dry and sound less german....)
2.mullard 12au7/12au7a 1958-1975 great low mid slightly recessed highs very smooth and weighty ,healthy gain.
3.brimar warm but not smooth less bass more upper mid lots of vintage british personality ,i prefer military/industrial (12au7a /cv 4003)versions since they have a lower noise floor (it's a very gainy tube)
4.ge jan military versions:well balanced sweet and crispy highs very low noise floor great clarity and definition,tames angry amps(too gainy or too sharp) .great tube and not so pricey .
5.rca 12au7a also a great tube more gain and upper midrange as opposed to the more transparent clean and hollow ge.