Anderson double hung series 8500 window

Both sides of the lower window single coil springs broke. The brake shoe is 2 1/4" long X 1 1/4" wide. The connection of the single coil is a single screw attachment into the track above the lower window when the window is in the down position. I can cut one side of the track rail to get the brake shoe out and install a new one......Do you have this shoe/coil assembly? If so , what is the price for 2 of these assemblies?.......At the time I installed all 12 windows in the house , these 8500 series were Anderson's top of their line. Now , they don't even carry them anymore and their 400 series is their best.

I looked over your web site a little more and it looks like what I need is your S161-10 brake shoe/spring assembly. The actual window is an Anderson 36" wide 40" tall double hung. So I'm thinking maybe the lower tilt in window may weigh about 12-15 lbs.??