This balancer is broken. The frame is bent a the bottom near the pivot lock shoe, Also there is a riot that hold the bottom of the spring near the pivot lock shoe that is also non operational and has pulled out. The pivot lock shoe itself is also showing damage. The top side has damaged plastic hardware as well. I am not sure if this comes as a complete unit.
from what I can tell on your site the balancer is a Series 795 Channel Balance Sash Support System. If it comes as a complete unit then I need a 3 sets (left and right) of these. If they come in pieces then I would need to research further to make sure I order the correct pieces (pivot lock shoe, channel, and block system).
This is a 36" channel (the pic was taken before I read to only measure the channel not including the hardware).
Cheryl