Need to replace pivot cams

Hello,

It looks like you might have a rusted pivot bar. If it's too damaged to remove, you can remove the screws, spray it with WD-40 and push it into the center of the sash channel since there is plenty of room to push the old part out of the way and install the new one. 

To identify the correct replacement, please remove an intact pivot bar from the other side of the sash or another window. Thank you!