The gutter extensions are available from any RV parts store or internet supplier...and can be found on Ebay, Amazon, Etc.
The come in white or black. I like the "long" ones as they expel the roof rainwater further away from the camper.
2012 Fun Finder XT 276 Toy Hauler & Harley Davidson Ultra Classic with Condor wheel chock
2014 Dodge Ram 2500 AT 4X4 Crew Cab 6.4 L Hemi, 373 gears, tow package, Rambox option, Revolver X2 tonneau cover, Equal-I-zer anti-sway hitch.