I think the output impedance will be just under 1k. Gain is presently set for 16dB (calculated). Although I burn off 6dB in front of the volume control. So changing R14 to zero will boost you to 22dB overall. That's more than I think is needed. Bandwidth may not go too low, perhaps only to 10Hz. Upper side will probably be something like 200kHz.
With just 22dB max, there is not enough gain for a HAGDAC. That wouldn't even get you to 0.5V. Anyway, the HAGDAC is being fitted into the DA-10. No suprise, that schematic is also very similar. The main difference is that I use a CCS for plate load instead of inductor. The tube is a 7788 and will have enough gain for 2V output. Oh yeah, and the heater supply is very big.