This seemed too easy to be theory optimal but I can figure out anything better. Hoping to see some magic to squeeze more silver out of my silver. The last cycles puzzle was too daunting so I'm glad that I was able to get it to the best I could calculate out. 

I expect I have 2 extra bonders, an extra arm, a unnecessary piston, and two extra track. That would put it at 470 somehow, but at least I got mine down from an initial 635 cost.