Help with tube tester

I have a chance to buy a bunch of electronic equipment from an out of business electronic store. I would do so because it includes tubes and some tube testers. It also includes some old recievers, preamps etc. He wnats to sell the stuff all as one lot. I am new to tubes but learning and would like to pick up a tester. The guy says he has a Supreme Radio Diagnometer Master Series #301 by Supreme Instruments in a nice oak box and also a Supreme Model #35 tester. Anyone know anything about these, such as possible price and value to me so that I can test the 6922, 7308 E88cc type tubes that my preamp uses? I know enough to know that I should go over and see the stuff and take down some model numbers and tube numbers to have a better idea of what has got. Any help even pointing me in the correct direction would be of great help. Thanks