The following TAD tubes are german designed and made in China under contract:
TAD 6L6WGC-STR
TAD 6L6GC-STR
TAD EL84-STR
TAD 6V6GTB-STR
As far as I know., all the others, including the plain jane EL84 (not STR) are relabeled. I believe that the ones designated with "STR" (Special Tube Request) are the TAD designs and made under contract. The one exception to this that I know of is the TAD 5AR4/GZ34 which is a heavy duty, hand-screened Shuguang brown base GZ34, but obviously meets the quality expectations to earn the STR designation.
Of the other types, these are the only ones whose origins I know for sure:
The EL34B is Shuguang
The E34L-CZ is JJ
The EL34-SVT is Winged "C".
As for the KT-66 -- my guess is either Shuguang or JJ, but that's just a guess.
Don't confuse the standard EL84 with the EL84STR -- not at all the same animal.
-- Jim