This balancer is based on the design from Balancing Tool.
I'm in the midst of building some high quality dynamic balancers and in the process thought I could help someone out who wants one if they can help me (sharing the expense of producing).
I know someone who has one of these devices and have seen it in action, I can say that it is very good, simple to use and very accurate.
Basically I will produce the mechanical portion of the balancer (including supplying the sensors) if someone can produce the circuit boards.
The files to generate the PCB are attached (the author no longer produces the device/parts).
You should be able to have any board shop make the boards with the supplied files, making a minor modification because a part has been substituted (original no longer available).
There are also online PCB options for small quantity / prototype runs so it should be relatively painless to have boards of quality made.
You don't have to populate the boards, making them is sufficient for me, I'm not greedy or trying to put anyone in the poor-house.
You are welcome to contact me to discuss the matter further.