Answering question for Vacuum Tube - 12AX7 / B759, Genalex Gold Lion

Product:
Vacuum Tube - 12AX7 / B759, Genalex Gold Lion

Question:
What is the best tube (3 units) for the Gas Cooker preamplifier MIC by Ridgefarm? Thank you in advance for the answer. e mail: k10dn@libero.it