Check out the following gears from Amazon:
http://www.amazon.com/exec/obidos/ASIN/B00GSYH5IC/uscahomednsor-20
http://www.amazon.com/exec/obidos/ASIN/B00N9GFMR8/uscahomednsor-20
http://www.amazon.com/exec/obidos/ASIN/B00TGH2T3O/uscahomednsor-20
http://www.amazon.com/exec/obidos/ASIN/B0012R4Z42/uscahomednsor-20
http://www.amazon.com/exec/obidos/ASIN/B0055NQXB2/uscahomednsor-20