I'm going to list more matched tubes (Amplitrex AT1000) the next few coming months. Some of these pairs are made by Mulllard in their famous Blackburn factory. I also sell EL34, 6P3S-E, EL84, ECC81, 5755, ECC82, EL82, 6P15P-EV, 6N3P-DR, 6N3P, 6N2P-EV, 6N1P-EV, 6N6P etc.