depends on your chain pitch..
it's either 12T (for #35 chain) or 10T (for #40 chain wich is likely to be the case)
measire your sprocket from one tip to the next.. if you end up with ~1/5" it'll be a #40 (esque) chain.
I'd say go for 420 chain wich will likely fit, but maybe you need the slightly wider #40
(measure the sprocket thickness to be sure)
but the clutch will be the same anyways.. a #40/#41 10T clutch.
and still... a TC (comet series 30 or clone off ebay) with a similar sized (10T #41) sprocket will add not only low end torque but also top end speed
'sid
PS also thread moved to proper forum and duplicate thread removed!
please do not start multiple threads asking the same question.