Window part block and tackle balancer

Thanks again for your patience. We may be able to replace this balance, though it will need to be custom made. Before we begin, can you confirm that there is no stamp on the original balance? I just want to be 100% sure. I would check the other balance on the other side of the sash, just to be sure. Knowing the stamp would be a huge help.

As for the top sash guide, yours is fairly unique, and we've had some trouble finding it. Can you tell me the width of the part that inserts into the side of the window? That would help us narrow down the list of possibilities.