It is stamped 2740
Thanks for reaching out to us! We should be able to help with this. Before I recommend anything, can you show us a photo of the inside of the metal channel where the innerspring connects to the pulley mechanism?
I'm not sure what you're describing when you say the hole pulled out of the block. Can you clarify that with a few photos?
Thanks! This is a big help. My top recommendation right now is our S350-28 with a 2740 stamp option. This comes with a 19-002 top and 15-004 bottom plastic fitting, so as long as those match then this should be a perfectly suitable replacement for your original hardware.
We always recommend replacing both balances in a given window at the same time. You never want to mix old and new balances.