Yes, that's almost exactly it, except for two minor differences:
- The lever will be rotating about an axis parallel to the screen rather than normal to it (which I'm having trouble figuring out how to sketch as well).
- The pulley itself will be driven by another lever, rather than by some force applied directly to the belt/chain. The belt will be fixed to some point on the pulley.
I'm more interested in mating the two components than modeling the link itself.
For simply mating the motions of the levers and pulleys you might be able to use gear mates. It might not be perfect but maybe it is close enough for your purposes.
If you are looking for a way to model the belt so that it updates dynamically as you move a lever, that will be very difficult. I think maybe the best you can do is draw it in context of the assembly with the ends tied to the levers. Then after you move the levers a rebuild would update the belt.