Your unit is fairly new. Take the fender, or pictures and measurements, to a dealer with a good parts Dept and have them order it for your specific unit. That's what I did when mine was newer. Got the exact replacement.
The other option is to either find some generics that would fit, or have them custom made. Several outfits do that, and their websites show you how to measure and order. Price didn't seem too bad and I'm betting they are better than the OEMs!
Scott and Liz - Southern NM
2012 Wildcat Sterling 32RL - w/level up (best option ever)
2007 Chevy 2500HD 4dr short bed Duramax w/allison
Reese Fifth Airborne air ride king pin coupler with Sidewinder