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Looking at your photos, I would recommend our Series 140 coil balance assembly. The stamp on your old assembly appears to be "9," so you might have our S140-09, but you should review the weight rating for this product to ensure that it can hold the weight of your sash. You can see that listed in the product description on its store page.

For the pivot bar, see our 26-398 and check our measurements to verify that they align.