Better amp or better tubes?

I have battleships from the 60’s, they are awesome, 25 years is young for the equipment, but a long time for tubes. And, the old stuff has lots of room and access to repair/replace anything in the future, the newer stuff is crowded inside.

1. re-bias existing tubes, assistance from Quicksilver, listen, any change?

2. I would definitely try new tubes. I have read a few articles that indicate NOS is not always best as assumed. I would try less costly version, DON"T LISTEN TO THEM. break them in 60 hours (don’t need to listen, just leave them on, walk away). Break in is a real thing, avoid a bad first impression prior to break in.

3. Then, put originals back in, listen to compare with new.

4. Verify with Quicksilver how to bias the new replacements in case some minor difference might effect things (probably the same, just eliminating any potential for a false comparison)

5. Listen to new. Nirvana re-discovered?
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Brent Jesse is a terrific source.

http://www.audiotubes.com/audtube.htm#aud%20list

NOS WE $3,100. each, based on rarity.

New current JJ $150. each, constructed like WE, ceramic base which I like.

I would buy matched JJ’s, and,see what change.

Then, if you have decided to keep the amps, and you have deep pockets, and have to know, Brent will let you return the JJ and buy the horribly expensive NOS. Confirm that with him ahead of time, if NOS not better than JJ, I would switch back.

Other member said "a 300B is a 300B". I certainly found that not to be true

my recent 6SL7 replacement. Original Cayin brand, unknown maker, sounded terrific. One side tube went bad. I have 2 tube testers. I had good used GE in stock, put it in, wonderful together with the used Cayin,

So, let’s get a new matched set. Picked Sylvania 6SL7WGT military from Brent: nooo! original used Cayin and used GE definitely preferred. Brent let me finish breaking them in (they did change a bit, which is why I advise breaking new tubes in first before listening.),

and eventually switch them for a matched pair of GE’s like my used one. (I got 2 matched pairs in case I live that long), at half the price, and Brent refunded the difference.
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And, I was using 6550’s, liked them, just for fun tried KT88’s. I prefer the KT88’s slightly.

Looking to change my stock tubes in my Primaluna Dialogue Premium 
integrated amp, so many  to chose input would be appreciated
Power 
Per amp  

There is a big difference in terms of sound profile when you get into better 300Bs.  As someone who imports 300B amps, a big question is what tubes to go with.  
At a modest price, the Emission Labs 300B is a huge step forward from the Russian mass produced tubes and is what I ship standard with out Diavolo amps.  These are $675.  

KR tubes offer a bit...more.  More detail, slightly better linearity.  Tighter bass but are a bit more expensive.  The base 300B is $1100, the balloon which has a larger envelope is $1300.
Sophia which are largely TJ Fullmusic are wonderful tubes. Last I checked, they have the Blue glass classics in-stock.  Those are best with the matching 274B.  What rectifier does that amp use?  They are out of most of their other 300B tubes but they said the have a few Royal Princesses in stock.  The blue glass are $1000 with the better warranty.
I sell these three brands at ArtAudio.us
Acme PSVane has a great line of products and only in the US, only sell direct.  Lots of threads covering off on different variants to dig into.  One note.  Anyone claiming they are selling new PSVane/Acme tubes better be reselling a pair they bought or their is a chance they are counterfeit.  Evidently this is a big issue on eBay for them.  Go to their site to buy direct.  

Takasuki’s are amazing tubes but a bit pricey.  Made in Japan, these are stock tubes on the Luxman 300B and are one of the best current runs.  The only issue with these is they tend to perform best at a lower bias.  They aren’t as sensitive as the EML Mesh which max out at 28w as opposed to the standard 40w but operate best running a little lower. These typically are priced at $2K a pair from what I have seen.  

I have an e-mail out to them to get a price and terms for importation.  There are a few current dealers. 
NOS 300Bs tend to be pricey as you know. I would be cautious about who I bought from.  

Hello Emil!  If your amp uses a 12AX7 input tube, change it to a New Old Stock Telefunken 12AX7.  I have a 300B tube amp, too and the new input tube made a remarkable. The distributor of my amp (Ele-Kit TU-8600B) says the other tubes don't make enough difference to bother with. At $200 or so, it's not expensive for the big improvement it makes. Keep Smiling.

Thank you all for your input. Much appreciated and something to think about.
@atmasphere 
all tubes have been purchased with the last 2 years with moderate use. I think they should be fine
@decooney 
Upgraditis. Too much free time on my hands. I can easily live with what I have now but isn't this the nature of the hobby?
My system:
Audio Mirror Tubadour III SE
LTA Microzotl Preamp
Quicksilver 300B amps 
Volti Audio modified Khorns
Full Loom Triode Wire Labs cables
@boomerbillone  
Input tubes are 12FQ7 . Recently replaced and purchased from Vintage Tube Services
Rectifier tubes are genelax Gold Lion 5AR4
@Verdantaudio
The Emmision Labs 300B looks like a tube I would be comfortable with considering it's price.