Hi Terri, I have quite a few of Squadron sticks myself though they are getting to the end of their days. I was not aware they had changed the design nor the make up but all is not lost. There are several makes out there for the conventional sanding stick - Albion Alloys for one but for the cost of a few commercial sticks you can but the materials to make an almost unlimited source yourself.
All that's required is a couple of sheets of hard-ish balsa wood, some double sided sticky tape at least 1" wide preferably 2" and a selection of silicon carbide wet and dry paper from 150 grit up to 1200 grit.
To make I find it best to cut some balsa to about 6" long and about 1-2" wide, lay it on the double sided then cut the tape to the outline of the balsa. Peel off the backing paper on the other side, lay that (stick) on the chosen abrasive and cut that to the outline too. Now you can cut pieces off in strips as you want them, the width and length to to suit your requirements - small as you like to as large and of course, cheap as chips to boot.
You can wet sand with them but it's best to wet the surface rather than the stick as it will release from the balsa once soaked but there's plenty more from where it came from
I've searched my files to see if I have any images of them in use but this is the only one I can find
In this case I have cut two small pieces off and attached them to a 'handle' from the same balsa with CA - just below the scalpel at the bottom and another above the drill chuck, RH side. If required the balsa can be pre-shaped to a degree before attaching to the double sided eg to create a concave or convex surface.
It doesn't answer your question directly but it does give you another option
Hope this isn't 'teaching granny' Terri
Regards - Tug
