spiral balance and pivot shoe ID

Hello,

Your photos resemble the (3/8") S900-29 or (5/8") S600-29 red tip spiral balances, depending on the diameter of the housing tube. 

How to measure the tube length of the S600 spiral balance.

If you need the pivot shoes as well, the 15-121 would be a good place to start but the determining factor would be how the specifications below compare to your shoe uninstalled. Take a look and let us know if you need anything else. Thank you! 

Alternate image for 15-121