Tube Tester

Valve test equipment per say is not really, "I have this much to spend on a  tool", kind of tool.

You get what you pay for. I'm sure there are some killer deals too.  Test equipment, and killer deals are NOT always a great combo..

The older equipment should be checked for accuracy. There are some great old testers, too. Remember, we're looking to match valves not just see if they are shorted, or weak, but matched,  I also looked into one that was laptop based, should work too.  I'm not gonna recommend a brand. I use a Hickok 539A.  It has the old rolo file, Very Art Deco, the A series..

Others will chime in..

Happy hunting

You really don't need a tube tester to enjoy your amp. 

Just buy from a reputable vendor. Matched pair power tubes in your case. Keep a spare of both power/preamp tubes. Tubes, especially the preamp tubes, generally are reliable, They futz out after a long time in service(years) 

$150 will buy you a $150 worth of nothing useful. That could buy nice tubes. The  tester a reputable dealer uses is not  like a simple hand held VOM.

Hi,
welcome to tubes.
what do you want to measure?
plate current, transconductance, noise, shorts, life of tubes, mu?
Type of tubes you want to measure are very popular and a good vendor can give you all the tests if required and match them too with a minimal fee.
If you want to start trading in tube market you do need a very good tube tester.
Tube testers are not all the same and do not measure everything unless you buy something more sophisticated at a cost.
Vintage Tube testers are indeed risky and most propably need service and calibration.