You can order the TAV with a #35 or #41 sprocket to match your chain size. As for the amount of teeth, I don't think they offer an option but the TAV gives you a variable ratio. The chain alignment shoudn't be a problem, the TAV is designed so it has the same alignment as running a centrifugal clutch outboard (that's how yours is mounted on that Briggs). I think the clutch life is excellent but some will debate that. On a 5HP engine it should last a long time.