while we can test the tubes, that may not really give you the information you are looking for, we can test to see if it is working, and get some idea of the condition but this won't tell how it sounds or how much use they have had. In addition, this would also take quite a bit of time to test that number of tubes.What you want them to do is test the 6SN7s. If they are good, that helps a lot! They should not be borderline. Don't have them test the power tubes, instead you can do that quickly by comparing them to the photos at this link:http://www.atma-sphere.com/Resources/6AS7G_Visual_Inspection.php
The reason is that if the tube is failing, quite often it knocks out the link or links in the photos. So a tester really isn't needed- the amp has a meter, if you are concerned about strength, and it can be used to get a relative merit reading of any power tube.