Tube recommendations


Hi all
The phono stage within my pre currently uses these 3 stock tubes - Sovtek ECC83, Electro Harmonix ECC81 & ECC88 (I think it's Tung Sol).
As I'm new to tubes which tubes would you recommend to be a significant  upgrade?

Thanks 
Rich

128x128infection
@chakster  Interesting commercial! I'd like to see an updated version by Seth MacFarlane!
Thank you for the kind words.  The price of Brimar tubes has generally been lower than the Mullard equivalent. To be perfectly honest I haven't bought a  Brimar Trustee  6060 in many years.  I would guess that because of their scarcity that  it will boil down to you and the seller agreeing to a price usually on Ebay.  I think that $100-$150 range people have mentioned seems appropriate.  I still have 2 or 3 of them.  Which brings me to the other point people have been alluding to.  Tube rolling is indeed a slippery slope.  I too couldn't get over the fact that with most tube rolls I heard a different sound.  I liked it so much that I have a stupid number of tubes.  I suppose I should sell but then I would want to buy them back again. 
Not only did I like rolling the various tubes I was using, I then just collected them for any of a number of reasons.  I also thought I should get back ups for them.  You see how it goes-
So you can stop now or forever hold your piece.  Quite honestly I enjoy my tube collection. However,  I am still wondering why I bought so many short bottle 6SN7Ws. I have about 16 of them.
I hate selling, many of these tubes are 70+ years old and might not sound great or even good in the buyers gear.  I don't want to deal with complaints and returns, I am not a department store.  At the same time I don't like it when the seller says no returns whatsoever, or as is. as found.  I  have been burned many times by unscrupulous sellers and have bought some real loser tubes .  One prominent example is my experience buying Western Electric 421As. I was buying them for a headphone amp I bought that uses 6AS7Gs and 6080 power tubes.  So many were feeble shadows of themselves, and I got the sense that the guy was selling it was simply trying to get his money back from the last guy.  I swallowed a few and decided to look for other brands of the same construction, e.g. domino plates. I refused to do the same passing on a weak tube.  That's what honesty buys you.
  When you say you preamp phonostage uses ecc81/12at7, and ecc83/12ax7, and ecc88/6dj8/6922, is this all the tubes in your preamp, or is this the tubes in the phonostage, with other tubes else where?  
   Your phono might be only one type of these tubes, and the line stage , in you pre, another type. To improve the phono, you would only really have to change the phono tubes, to have the greatest effect.
    As far as sonics, only listening to the actual tubes in your preamp circuit will tell, everything else will be a general rule of thumb, which may, or may not apply. Most vintage tubes, tend to sound better, than most modern tubes, generally
   I am a tube seller with over 40 years of experience, with buying and selling tubes. I have built a bunch of tube gear, and the same tube sounds very different, in different circuits.
   If you can afford it, pricey NOS tubes, should always be the choice, as their value seems to go up. So if you did not like the choice, or found a set you like better, they can be resold. If on a budget, then vintage RCA, GE, and the like, can make a worthwhile improvement inexpensively.

    
@fletchj  - as i mentioned in my initial post this concerns the phono stage module within my Octave HP700. 
The pre already has Telefunken tubes.

I've now replaced the ECC81 & ECC83 in the phono stage module with NOS Telefunken. I cleaned the pins & as soon as I tried a record it was evident that these are superior. Even at this early stage there is far more detail, depth, increased low end & lower noise floor. 
I'm looking forward to how the sound develops...

Thanks again to you all, I really appreciate your input in helping me to choose these tubes.

You're welcome. Are you certain I can't introduce you to some o return used up crap from the last Shmegeggy, I bought them from.
Seriously, I have a major surgery coming up but in 10.5 weeks I'll be back, and for the first time seriously consider selling some of my tubes, only I will be honest about it..  I will do it through normal channels and I may indeed have an extra Trustee 6060 pair. I'll be sure to advertise them at that time.As long as I am writing in a dead thread, I will say that some microphonia in 70 Year Old 6SN7GTs isn't always a bad thing. I'll start a thread on that one, because I genuinely think and believe it helps with stage width depth and other  imagery, honestly.