I ran the kit last night with 4 regular alkalines AAs and it ran for over 5 hours non stop before I shut it down. They were batteries that I had used before, so brand new ones should theoretically run for 6 or 7 hours, but don't quote me on that. I was going to try 4 non-rechargeable lithium AAs, but I forgot them at home. I will try those tomorrow, but given that the standard alkalines lasted over 5, the lithiums should do more than that easily.
So it looks like the entire kit should run off of 4AA batteries (i don't know if 4 rechargeable AAs like NICAD and NIMH will work since their normal voltage is 1.2v not the 1.5v that alkalines and lithiums have). I also shrunk down the size of the PC board down to 2 inches square, so it shouldn't take up too much room inside the helmet. Right now I don't think I will provide an enclosure for the board, but I may later on if I find one that I like.
Once I get the boards made and am ready to start the run, I will post here. I will be using sellbuddy for these kits just like my other ones. I haven't decided on a final price point yet, but it will be less than $200, and it will include the servo, servo extension, controller board, battery holder with switch, wireless transmitter, as well as accurate alco mpa106f gauntlet switches. These switches are momentary ones, not push on/off ones like used in the film, but they look exactly the same.