Can't stress this enough on the Brimar 6BQ7A tubes... give them plenty of burn-in before passing judgement on the sound. When I first bought these, I rolled them in and thought they were awful. Other people have had the same experience. After only 7-8 hours there was a noticeable difference in sound quality, and after a couple of days of use they really settled in well. They are excellent sounding tubes once burned in.
They sounded very hot and distorted in the midrange initially but I think they are beginning to even out into something special. I had my doubts about these tubes as I had heard Brimar was often rebranding tubes, but for the price I paid they are a steal.
The vintage 6N1P's I got along with these are amazing as well. I think if you get lucky with a good pair of Russian tubes you could quite possibly endgame with your Lyr.
I'm beginning to think I am close to the end of the road here.