MW Twinseal Window Balances

Hi Dawn. It looks like the outer tube of your old spiral balance was 25" in length. If so, you need either the S900-25 3/8" diameter balance, or the S600-25 5/8" diameter balance. You'll need to measure the diameter of your old balance's outer tube to confirm which balance you need. You'll then have to choose a color tip option, which basically indicates the weight range the spiral balance supports. Your old balance has a white tip we do not use; to know what color option to pick, weigh the window sash these spiral balances support. You can then match that exact weight with one of the weight ranges listed next to each color tip option under the product description of either the S600-25 or S900-25 shop page. 

As to the other parts you show: for the pivot shoe (the plastic block that the spiral rod connects to, and from which the window sash pivots), there's quite a few different possible options. The best thing to do is to remove the old shoe and measure its width and thickness. Give us those exact dimensions and we should be able to narrow down what shoe you need. The video below shows how to remove and replace pivot shoes. 

I still think the 26-366 is our best match for the pivot bar, yes. Unfortunately, I still need more data on the pivot shoe before I can say for sure. That was the piece I needed to see removed, not the bar. Would that still be possible? I just need to know its width and thickness. Seeing an undamaged version would also be preferable.

I do agree that you have our S900-25 balance, yes. With a sash weight of 16 pounds, you can use the Red Tip option.

That's perfect, thank you! This shoe appears to be a match for our 15-219. I think this may be exactly what you want but look over its dimensions to verify.

Dimensions for 15-219