Best place to buy tubes


I have a Audio Research VT-100 MKIII and it's time to take out the old tubes and put in the new. Were is the best place to buy the 6550's? I would rather not spend the money that Audio Research is asking, so I thought there must be some one how is testing there tubes at the same quality as AR.

Thanks
hrunge
Many successful retubes via tubestore.com. They are also helpful on the phone.
Kevin at upscale really knows his stuff. He will suggest several alternatives and his advise is good.
I called Andy a few times today but no answer.
I'll try again...

Thanks for the input,
If you want regular modern production tubes few people match Jim McShane he is on AA's tube asylum as a dealer, Also Brent Jesse he has great service and more NOS. I also like Tubemonger.com for NOS very honest good knowledge base. What ever you do there is virtually no good reason to spend 3X the usual cost for factory supplied replacements if you use a dealer who really tests the tubes. The ones I mentioned really do. If you can bias your all set. There is nothing magical about it the good dealers reject the bad tubes also.
Andy will be closing up shop very soon, FYI. I just reloaded a complete set for my MP-1.
From Andy Bowman of Vintage Tube Services (616)545-3467. He is a one man operation so if you don't contact him on the first try, keep trying. He is the man for NOS tubes. He also has a very informative web page: www.vintagetubeservices.com
Andy Bowman at Vintage Tube Services. Tough to get a hold of, but absolutely the best in the tube biz.