Re-tubing a McIntosh power amp


I have a McIntosh 275 VI tube amp that I am considering changing out the tubes. Not interested in rolling, just upgrading from the stock tubes that it shipped with. Don’t want to go exotic ($$$)  just trying to replace them with some upgraded, reliable tubes. Have any if you done this recently? Looking for suggestions on brands and reliable, fairly priced  tube sources. Thanks!
cincyhound
Also Roger Modjeski ( rip ) built some very advanced testing and grading gear for modern tubes - I have a set of his RAM KT.88 in my RM-9 and his super precise low noise driver ..

RAM tubes
RAM throws out or returns some 90%…. Sounds like the definition of crap shoot…

I played about with this a bit on my CJ Premier 11a.  Found the GL KT88s to be by far the best.  Don't know whether or not your amp allows individual tube biasing but if it does, it sure saves on not having to but matched tubes.