I designed a simple pulley:
Here’s the STL file:
stooge_wheel_pulley_44T.stl (880.3 KB)
It’s 44T, 19mm wide. Works great with M4x25 countersunk head bolts since they go almost all the way into the hub (the thread is 10mm deep). I have a parameter driven model and can change both the number of teeth and the width. Let me know if you need an STL with another parameters.