Tubes for leben cs600 ?


hi everyone .after i bought my used leben cs600 ,i found that my speakers (devore nines) have lack of details and dynamic.
i thought that the leben is the problem and i considered to buy the line magnetic 218 ia amp,after i got response here in the forum and suggestions that to replace my tubes in my leben better of buying a new LM audio amp (218 ia SET).
i choose to stay with my leben and replace the current tubes that are :
4 - electronic tube 6cs7 (made in usa)
1 - sylvania 6cj3
4 - goldlion kt-77 genalex made in russia.
the 6cj3 look black half of her and the 4 pre tubes (6cs7) look old need to replace. i like to replace all the tubes in my leben 9 new tubes but i dont know what to order for the best resault and to slove the details and dynamic problems ?my dealer in israel say all new 9 tubes of original what leben company put need to be in my leben and it coast to me 400$, or there is another alternative to order and what will be the best for my leben ,i still not know from where to order and what tubes to choose and why
please help me this problem, wait for response
thanks alot.
bolero32
Anyone have to change tube after buy this amplifier in.paying 8000 usd.
 İf you sell it you have to use suitable tubes inside there.
I bought an Leben cs600x paying 8000 usd in Turkey.
I used it 130 hours. I waited burn breaking but no treble sound no transparency no details.
Why I research new and different tubes for that amplifier. I paid 8000 usd. is not enough?
I will pay how many price more to get real sound?
Leben cs 600 x is an catastrophe. Real catastrophe.
I don't advice anyone. I can send you the sounds differnces beetwen 1000 usd Chine  tube amplufier and 8000 ysd Leben amplifier . 1000 usd Cine amplifier much better than 8000 usd Leben cs600x
I purchesed Leben cs600x at 2020 july. There is no treble frekans no dynamics no resolution. Why I research new tubes for it. Why. 8 din't know what tube suitable for Leben.
Conclusion: Leben is not good amplifier. I payed  8000 usd from Turkey distrubutor.