tube suggestions/ brand new to tubes

I will repeat what others have said.  You need at least 50 hours on the tubes and lots of listening times.  I like to listen during breakin at least periodically for the changes. Tubes are a bit like gardening.  It is a slow process to see or hear change.  

I recommend new tubes.  They are making news tubes specifically for audio and honestly, I think they are better than playing the made 50 years ago NOS game.  IMO, new audio tubes made with modern design tools and equipment are more accurate than a tube made 50 years ago for a radar or basic radio.  Tubes already add in tube flavor and many NOS go too far into tube land.  Now if you need or want that go for it, but I prefer the accuracy of new tubes.  For small signal tubes, I have found Rays Reserve and Gold Lion Gold Pin to be the best in the 12AU7 tubes.  Great clarity and still the holographic sound of tubes.  I find 40 to 50 hours is needed to for break in for my ears on my equipment - might get better beyond that, but if so, it would be small and I am on to different upgrades.  Finally, my tube preamp did not like being paired with the Gaia isolation feet - the sound was flat and without sparkle and I lost soundstage.  

@12many raises an excellent point... fresh tubes (of any make) sound so much better than tired tubes with lower mu (transconductance) resulting from use and natural degradation ... tubes certainly do wear down over time in circuit, and the effect is aging tubes is often less treble detail, air/soundstage and visceral impact

this is especially important when buying old stock tubes that are ’pulls’ from antique equipment... think of it as buying used tires off an old car... in the case of tubes you need a proper tube tester to assess, rather than a visual inspection of tread depth etc etc

Best advice I can give is only use exact specification tubes.    Don’t go on someone’s suggestion,  if in doubt find a resource like a late model  Hickok tube tester owners manual,   

There are charts with exact substitutions , like 12ax7 and ecc83.  One is the US name and the other is European. 

There are close substitution charts too but I would only use exact types.  Tubes that gave the same electrical specs like current draw and voltage.    Lots of date that can help make good, safe replacement tubes without risking damage.  

Another vote for Andy at Vintage Tube Services.  As with everything in life, you get what you pay for.  With Andy, you are paying for knowledge, expertise, and somebody that CARES which tubes are the best match for your gear.  He’s an acquired taste, but I like dealing with no-nonsense businessmen because I was also one.  I want brass tacks and the bottom line, and that’s Andy.

That said, when you wrote this preamp will be in a system playing mostly rock and roll, are you talking about 1970’s classic rock and guitar heavy current rock?  If so, you should talk to Andy about these particular tubes to see if they match the sonics you are seeking:

12AU7 --  NOS Mullard, Telefunken, or RCA.

12AX7 -- NOS Amperex or Mullard.  NOS Telefunken are the best, but pricey.

12AT7 -- Again, NOS Telefunken is the king, but open the wallet and try to find them.  A good alternative is NOS Siemens or RCA.

As others have said, give the tubes you have time to develop a sonic signature before making any moves.  See if they provide a sound that is appealing to you.  If not, or if you want to experiment, start the tube rolling game and discover the excitement of being a "Valve Head".

https://vintagetubeservices.com/

P.S.  You sign off with Robert TN.  Are you in Tennessee?  I was born and raised in East Tennessee and graduated from UT-K.

Like a broken record I will repeat:

Get thee a Tube Tester, otherwise you keep yourself blind.

Test new ones when you buy them. Test them periodically, i.e. every 6 months. If a problem comes up, be able to find or rule out the tubes.

Find shorts (rare but they do occur), weak strength, unmatched strength.

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I might take a chance on one of these

This just listed, not tested, seller has no tubes, 30 day returns,

https://www.ebay.com/itm/267730051303?mkrid=711-53200-19255-0&campid=5338381866&toolid=10001&customid=820ac094-81ea-11f1-83ef-306561363937

tested, works, read the description

https://www.usaudiomart.com/details/650330617-beautiful-heathkit-tc-2-tube-tester/