Need help with replacement parts!

Hey Lisa. This looks like a 15-191 Pivot Shoe, as well as 1/2" thick Series 160 Coil Balances. Springs stamped #5.5 are replaceable with the S160-05 5.5 pound springs, whereas the #6.6 stamped springs can be replaced with the S160-06 6.5 pound springs. If there are two springs on each side of the window, that would equal 12 pounds of support on each side, for a total support of 24 pounds. You may want to double-check the sash weight to see if it falls closer to this number. Unless you had trouble closing the windows or keeping the windows closed prior to the springs breaking, the weight of the sash should be within 1 pound of 24 pounds. 

If your old housing is undamaged you can reuse it; otherwise see the 15-150D. Let me know if you have further questions. 

If your sash is only 17.2 pounds then the springs you have now are way too strong. You could go down to using just one 9 pound spring per side, which will give you 18 pounds of support. That should be sufficient. See our S160-09.

These balances don't come with instructions but they're very easy to assemble. The "T" shaped end of the spring feeds into the pivot shoe at one of the top two corners, then twists to lock in. Each subsequent coil (assuming you use more than one) then lock into the spring below it like a barrel of monkeys.

There is nothing that connects the springs to the housing. They are loosely cradled at first, but are secured in place after the cover is screwed into the wall.

As for whether the piece that came out of your shoe already is part of the spring, I cannot say for sure. It's entirely possible, but I can't see the piece in question to say for sure.

If you are using only one per side spring, then I'd suggest using the 15-150S single spring support.

That's fantastic news! I'm so glad that everything worked out.

Thanks again for the business, and please don't hesitate to reach out if we can offer any further assistance.