Dont' bother with Upscale - unless you bought your BAT piece there, they won't sell any decent 6SN7s to you. (just their policy.) the Red Base 5962 are pretty sought after, though a lot of people dont' think they are the best of the 6SN7 types. Also, the ECC34 are not really a direct 6SN7 substitute - I'd check with BAT on those... if they work - great, but be aware there are differences, electrically, between 6SN7 and ECC34...(I think CV1988 is more the direct mullard substitute for 6SN7). Have fun, tube rolling can be one of the best parts of owning tube gear.
-Ed
