MW stamp on lock?

Hello there! Thank you for reaching out to us. I'm afraid we can't assist with the damage to your window but we should be able to help with the balance. I see a type of attachment here in your first photo but it's hard to make out. Would you be able to remove it from the window and show us a photo? 

As for the weatherstripping, can you remove an undamaged sample and show us a clear photo of the end profile? If it's pile, we will need you to write out the pile height and base width.

Unfortunately, these photos don't show the shoe. The window sash will have to be removed so that we can get a good look at it. 

This is perfect, thank you! Our Series 795 channel balance can replace your old assembly as long as the spring diameter is 1/2". The video below will walk you through the replacement process. 

Let me know if you have any questions!

No problem; good luck with the repair!