Tube Testers. Which to buy and where?


I'm hoping I can afford a tube tester, used. I'd love to be able to test output and input tubes, 6550, KT88, EL34, etc.
I've no idea how much they go for. I've looked on A-gon here, but I've no idea if these are worth pursuing or junk.
I'd even consider new if new could be had for a few hundred, or preferably much less. Then again, I'm thinking if they were that cheep, maybe everyone would want them?

Any input is appreciated.
Thanks,
David
rolloff
Anybody know anything about a unit labled NRI Professional?

I bought it lately at an antique mall.

Thanks
Woody
I have a B&K 650 Dynaquick out in the garage. I used to use it to test 6550 and small signal tubes but have no more tube equipment. It did a good job. matching sections of dual triodes such as 12AX7 etc.I would love to have it out of the garage.
I think the TV-7s are cool looking. I used to see a lot on Ebay.

I bought a simple to use B&K Dynajet 606 on Ebay last year for $50. It has served me well.
Cadet1,

I'm looking for a tube testor as well. Especially for 12AX's and 12AU's. I'll help you get it out of your garage. What do you want for it?