JT, I love guns and have a few myself. But I don't see many in the market for a .338 Winchester. It certainly looks good, and I'm sure it will be more accurate than me, but the chance of someone on this forum wanting something like that and having a kayak trailer to trade would have to be very small. I have a 5 kayak trailer that I built myself from a flatbed trailer, and I wouldn't make that trade. I know quite a few guys that kayak regularly and many that have multiple kayaks, but only a couple that have trailers for 4-6 kayaks.
I recommend you sell your gun in the main Classifieds (shouldn't have any problem selling there) and build a trailer. I can email pics of mine to you if you want some ideas.
Good luck with it.
Dad took me fishing when I was 10, and I've been pretty much hooked since. He went to be with God on August 14, 2012. I miss you, Dad.