String Trimmers

I have a Model #128C Trimmer, 2009, Serial # 09119N1000120(08:47).

This serial number does not seem to match the serial number nomenclature as shown under the Serial Number section on the Husqvarna website.

I need a replacement carburetor. On different websites under the model 128C there are several series listed (2008-12, 2009-03, 2009-05, 2009-08, 2010-03) etc. Most call for the carburetor p/n 545081850, but it seems the later(?) series call for the p/n 545081848. The 545081848 is much cheaper and more readily available. Are these carburetors interchangeable? If not, which is the correct carburetor for this serial number 128C trimmer?

Thanks.