Our house was missing a drive rod for one of our blinds, so after about a minute in OnShape this is the simple fix I cam up with.
I recommend printing in PETG for its flexibility. Print with a wide brim to keep it from falling over.
Rod height is 253 mm.
Printed on a Bambu Lab X1C. Speeds were set at a conservative 80mm/s.
The author marked this model as their own original creation.