Do I have to replace pivot shoes?

I will be replacing my spiral sashes with the S900-28 (both color tips for different size windows). I have two questions:

1. Do I have to replace the pivot shoes, or only if they're broken? If I have to replace them, would 15-045 be the right one (I have attached a picture because I wasn't able to remove the shoe at this time since I would have to cut an opening)?

2. The other picture attached are plastic pieces that fit into the channel to cover it. Do you offer these also? The long one is about 30" long by 1.5" wide (it is bent to that size and clips into the sash channel). The short one is a clip about 2" long by1.25" wide (it has clips on the back about 3/4" wide that clip into the sash channel at the top to hide the screw in the balance).

Thank you for your help.

Eric

Paul,
Thanks so much for your quick response. Your right, the 15-046 does look like a better match and after trying to measure the channel it looks like the right size.

As for the spiral sash, I measured the vinyl cylinder and they're definitely 3/8" (with a yellow tip). They are original "builder" windows from about 1991. Should I replace them with the 5/8" (S600) or keep the original size of 3/8" (S900)? As for the tip color I'm planning on using the red tip for the smaller windows (about 12-14 lbs.) and the green tip for the 3 bigger windows (couldn't weigh them but they're about twice the width of the smaller windows).

Again, thanks for the information and help. Once I replace mine I will definitely refer the neighbors here if they decide to fix theirs.

Eric