KT150 tubes

About 2 months ago I got a really good deal on a brand new pair of Quicksilver M120 amps with the KT150 tube upgrade. I was in the market because my beloved VTL MB125 amps were starting to have some issues and these presented themselves as a direct plug and play in my system, so after the break in of around 200 hours have realized they will remain a part of my system even after my VTLs are returned from being repaired. Now my dilemma is this, these two pair of amps both are very special of their own wright and bring different things to the table in my system, with that said am wondering when someone other than Tung Sol might be making KT150 tubes to roll in these amps to try to fine tune them even more.