Tube Rolling with 6SN7 tubes...?

Here are a few options.
RCA VT-231, I think the Grey glass tubes are closser to what you want than the black glass.
National Union, I prefer the black glass but think from your post the grey glass again would work for you.
The CBS brown base has a sweet midrange.
The KenRad VT-231 has a nice midrange and very good bass.
The Brimar CV1988 has a nice midrange also.
You can go www.head-fi.org and do a search in the amplification forum for a thread titled
The 6sn7 reference thread
It has about as much info on these tubes (and all 6sn7 tubes) as you will need.

If you like the sound of the Sylvania tubes these are both drop ins for the 6sn7s that sound at least as good (I think better) than there 6sn7 counterparts. They can be found for 8-15 bucks.
7N7 and 7AF7 try a few.