Jafox's response is spot-on. The 6922s from ARC are likely Sovteks. ARC will test them and screen for low noise, so they do offer value. Other tube vendors will do the same, some for half the cost you quoted. Fwiw, you are not limited to 6922s; 6DJ8s and 7308s work fine in the PH5 and PH7.
Arc-PH-5 what tubes should I use
My unit takes 4 6922's. My dealer is trying to sell me these RAM tubes that are low noise for 90.00 each. It seems to me that this is on the high-side. I can buy tubes from ARC that are 35.00 each. Do you think these low noise tubes are a gimmick or do they really work. Were looking at a price difference of 220.00. Is it worth it?