You'd better order the same model in case it won't fit your phone. If what you've ordered is LCD screen and digitizer with front housing, then you may have to change it, because the front housing of one model is not compatible with other models. If the item you've ordered is without housing, you could transfer the front housing to the newly bought LCD screen and digitizer.
Here is one site with all models of Samsung Galaxy S4 LCD screen and digitizer with front housing. http://www.etradesupply.com/samsung/galaxy-models.html