Replacement for left & right sides

Thanks for posting. I could not locate the exact vent hinge parts you show in your photos. I went back to look at some old catalogs from 1972 and I couldn't even find a match there! Now, yours does look similar to the 39-539 nylon cam, but your has a type of "off set". Not sure you could adapt it to your window. Take a look at it, as well as the 39-538 and 39-537, and see if you think you could adapt any of these to your window. If all else fails, I am afraid you may have to consider a new window entirely. Let me know what you discover.