What I would try.

http://www.beltingonline.com/10-toot...ey-al27t5-4916
http://www.beltingonline.com/36-toot...ey-al27t5-4932 *
http://www.beltingonline.com/36-toot...ey-al27t5-4932

*But I prefer a smooth pulley on the disk. Call it a quirk.