6Q7G as driver in RH807

[2bamp]

I have started collecting parts to build an RH807, and I have some very strong used 6Q7G as well as some NOS 6Q7GT.
So, looking at the RCA manual, it is a single triode similar to the 6SQ7 and 6AV6, so thus similar to the 12AX7. My GE Essential Characteristics book lists an amplification factor of 70, slightly higher than the 12AT7 the circuit calls for.
The values in the GE book in typical operation have an plate resistance and transconductance that is nowhere near the 12AT7, albeit pretty close to a 12AX7.
I was going to use a pair of 6AB4, but would this make an appropriate driver? The aesthetics are certainly there, but could changing the plate and cathode loads compensate somehow? I don't have a good understanding of how the negative feedback will influence the change.

 

[DF96]

6Q7=6AT6=0.5*5751. mu=70.

6AV6=0.5*12AX7. mu=100.

The 12AT7 is very different.

 

[mike567]

Won't handle the current required if building "RHxx" amp.

 

[2bamp]

Are there any predecessor tubes to the 12AT7? I haven't come across any, but I really want to use something different, and more interesting than a 6DT8 or pair of 6AB4.