I have completed a batch of ispindel's and have some extra if anyone is interested. Price is $50 (with US shipping included). The ispindels were built using the Cherry Phillip v4.0 PCB and have the 6.3.1 firmware installed. They will include a brand new battery and have already been calibrated using multiple measurements in sugar water. I have verified that they are all connecting to my instance of ferementrack and are reporting gravity and temperature correctly. Send me a PM if you are interested.