I have a good tube tester and have been able to verify tubes sold by Brent Jesse, Tube Depot and Jim McShane.
The big problem for me is I haven't yet built a rig to test for noise as this is important for tube phono stages. So, the only thing I can do right now is use the phono stages to test for noise. The above three vendors will sort for noise if you ask them and I've had good results.
When I purchased from Viva Tubes, I saw they had no optional noise testing. So, when I placed the order I asked them to sort for noise. The tubes I received were unacceptable for noise. They ignored my emails asking for a refund. That's why I don't recommend them.

