Recommend new EL84 tubes

Hi all, I have been contacted by a good friend asking me to source 8 X EL84 for his Manley Stingray which is a parallel P-P integrated amp.

He has had the original valves for about 10 years, which I think are rebranded Sovteks or Electro Harmonix 6Pi14Pi-EB.  

2 sets of matched quads will do. He is looking to improve on the originals. The amp has individual bias pots for each valve so perfect matching is not paramount.

He also needs a pair of 12AT7's. Best quality needed for this position.