You didn't say what size you were looking for 32t or 36t. Here is a Shimano tech doc on your FC-M443-8, which shows the chainrings, model numbers and compatibility. http://techdocs.shimano.com/media/te...9830647957.pdf. The 32t middle CR is a #Y-1D S98010, which I found at Cambria http://www.cambriabike.com/product/s..._108668076.php. The 36T chainring is a #Y-1HL 98130. This apparently is more of a rare bird as my initial search was negative; if you need the 36T you may need to drag out the file.