Well at my old job we had a "junk box" just brimming full of ADB cables, keyboards, track balls, even some of the old, 747 wing-sized Wacom tablets, and other goodies from the Apple beige era. There's was a sign on the box's outside marked "take anything here... free!" Every once and a while you'd see someone digging through, untangling cables, for something. If I still had connections at that old place I'd get you one and send it to you COD for just the shipping cost.
$30? Must be a peecee, you can get more than that for an old Mac, any old Mac, if you tried (excepting maybe those odd performa 6320, 6332, 6431, 410, 420, etc. models).
C
PS If you see a TAM (Twentieth Anniversary Mac) some fool is selling for $30 and it works let me know, I'll buy without haggling!