I am not sure if this standard Catalina stuff, but our pleated shades fasten down on 1" diameter Velcro discs made of a stiff plastic with a single screw hole. Sailrite has a 1 ⅛" version but I am hoping someone has sourced a smaller one.
If I understand what you're looking for, Staples.com has all kind of options for velcro. Some might lend themselves to adding a screw if necessary for strength.
https://www.staples.com/velcro/directory_velcro?deptFid=Department_3A_22Hook!and!Loop!Fasteners_22
Thanks Steve. These have a stiff plastic substrate and I think the Staples discs are all soft. I'll keep looking.
I bought the Sailrite discs. Replaced them all with white discs. Works well and looks good. Also shortened some shades by fastening one pleat together. Can't say I remember exactly how. It got rid of the sag.
Jim
for what's it worth mcmaster has stiff hook/loop discs, but not in 1" either. if you don't want the 1-1/8" you could go down to 3/4"
https://www.mcmaster.com/hook-and-loop-discs/form~disc/