Broken cam

You'll need the 15-177 Coil Balance Shoe and Series 152 Coil Balances to replace this coil assembly. The coil is attached to the shoe using the 33-072 screw. 

I believe the "pin" you are referring to is the pivot bar. To determine the correct replacement, I'll need to see a photo of the existing hardware.

Alternate image for 15-177

In regard to selecting the correct coil weight option, you'll need to look for stamps/markings on all of the coils. If there aren't any, please take a look at the video tutorial below.

If you can reuse the covers/supports, that would be suggested but the 15-143, 15-144, and 15-145 will work to replace them.