Coil Shoe Balance

Hello and thank you for your website. It's helping me find parts I need to fix my window. This is my first time ever trying to replace shoe both left and right and both latches on a window. I am pretty sure I need 15-177 shoe and it looks like side natural so I would buy two, one for each side. I have attached two photos for you to triple check for me please. Also, as you can see in the pics. the system is broken so I can't use a screwdriver to unlock and remove the shoes. Any suggestions on how I can remove the broken shoes? it's in the locked position. Also, can I buy the heaviest 8 Ibs coil for replacement? Is there any harm in that? I have no idea how heavy the window sash weighs but it feels heavy to me. These are at least 20 year-old Alside windows. Appreciate your feedback. Alex