Nice set Tim! I have a 709 that was my first early TV find 40 years ago. The knobs are actually quite common and look similar to the VT71 knobs. The tuning knob is the most unique as it has a little brass dot for the indicator.
You can see what the knobs looked like in an original brochure I scanned:
http://www.tvhistory.tv/1946-49-AUTOMATIC.htm