Only known parameters so far is what seems to be called generically
"perforated tape" steel or bronze, 1.5 inches wide , thin enough strip
to comfortably curve around 12 inch diameter pulleys . Unknown is
whether round ball or square studs on the pulley matching round or
square line of central holes.
I'm assuming there is an optimum "sprocket" design spacing given these
other parameters, radius of curvature, torque/force transfer per ball ,
the hole spacing is the parameter we're after, but not found.