Hello tcsmythe. Yes, the WF-7840 can load 13" x 19" paper from the rear paper feed. The thickest paper tested on the printer is Epson Premium Photo Paper Glossy which weighs 79 lb. For cardstock, we recommend using paper that weighs around 44 lb. You can try a cardstock paper that falls in that range or more. However, your results can vary when using thick or heavier paper, as these recommendations are for Epson paper only since we have not tested 3rd party media. Regards, Kevin - The Epson Team.