Wasco Window

Hey Yui. This looks like a 15-177 Pivot Shoe, which uses Series 152 Coil Balances. For the coil spring, you'll need to select a spring weight, or basically the weight the individual coil can support. Look for a stamp on the old coil that indicates the spring weight needed. If there is none or you are unsure, please give me the exact weight of the window sash, and I can work out what you need. 

So, a 1-1/4" width is very, very common, but it's not universal. I've seen shoe width vary anywhere from 15/16" wide to 1-1/4". Just something to be mindful of if you have other windows that encounter this issue. That said, 1-1/4" is by far the most common width I see.

As for this lock, we have a few different options that may replace this, depending on the distance between the two installation holes (measured center-to-center). See our 90-274 (2-1/4" c-c) and our 90-278 (1-1/16" c-c) and see if either of these would work. Also be mindful of the backset, which is 11/16" in both cases.

Dimensions for 90-274

Dimensions for 90-278

You're very welcome! I was happy to help, of course. And I appreciate your kind words, too! It means a lot. I will make sure to send this thread to my boss for him to review!