Lector 7T and tube rolling



I'v got this nice CD player, but would like to have even smoother highs. It has originally CVC Chelmer valves (12AT7) and I wonder if old Mullards, RCA, Siemens or other NOS would change this?
Is it important to have NOS from the 60's or is tubes from the 80's almost as good?

Thanks!
ole_s
Here are my suggestions:
1. Isolate the CDP well, and it really means great differences in musical presentation. I put them atop a BDR Shelf with BDR cones, and that was much better than the Seismic Sink (older model) I have.
2. I tried many tubes. So far I like the Valvo 6201 (blue lable is a bit better than the white)and the cheap GE 5 star also gives a more lively sound. Siemens ECC81 or ECC801 gives a more linear sound with solid bass.
The distributor has spoken with people who have tried many, many different tubes. At the end of the day, the stock tubes turn out to be pretty darn good, which says Lector did their homework. As a new Lector dealer eagerly awaiting the CDP-7TL any day now, I'll be trying other tubes, along with isolation solutions.
...again,i read it's isolation sensitive. Did anyone experience imporovement by isolating the unit.If so, which way worled best?
On tube I thought the stock tubes did a really nice job, but I did upgrade to NOS Telefunken ECC801's. A bit more refined sounding.

Power cords can really add something to the party as well, I tired an Actinote (slightly better than stock), zCable Red Lightning (worse than stock), and ended up splurging for a Shunyata Anaconda Alpha Helix (big time improvements).

Then lastly on isolation, I went with a Silent Running Audio VR series isoBASE 3.0. I thought the base took things to another level in particular with the bass. But also some other areas. It is not the cheapest isolation method, but I feel it was worth every penny. Now I just wish I could afford a pair of these to go under my monoblocks as well. But yes teh rumors of you needing good isolation beneath the player are true.