Gold Pin KT66 Retube kit for the later model Vibro King. The Gold Pin / KT66 kit uses a matched pair of the JJ KT66's for power, a JJ 6V6S for the reverb driver and five of the Gold Pin ECC83S's with one being current balanced for the phase inverter in V5.
The Vibro Kings are adjustable bias and all you need to adjust the bias is a bias probe and a multimeter or the Eurotubes "Pro One". All of these are are available in the "Related Products" tab. You can use the Deluxe Reverb bias video for reference. We typically bias these amps between 36 to 44mA with the JJ KT66's. The video below explains the difference between bias probe types.