New Tires – 2014 Polaris Sportsman 550

Looking to get a set of new tires for my 2014 Polaris Sportsman 550, I want to try to keep the stock rims but having a hard time finding the same size tires. The rear is 26×10-14 and the front is 26×8-14 / Can I go bigger with out any issues? Recommended Size?? Looking for a woods / water / swamp tire. New to the forum so any information is great.