Most of the Triton or Newman SledBed aluminum trailers you'll find are made for snowmobiles. I just bought a tilting SledBed because it was only $1300 new.
The cat is for river research, so it has various odd spars and mounts for electronic gear, and a big trolling motor up front.
The aluminum snowmachine trailers work fine for boats, except snowmachines are quite heavy up front, so the trailer axle is set forward of where it should be for a raft, and the trailer won't balance right (have the proper amount of weight on the hitch). A cheap and temporary fix is to put a sandbag or two on the front of the trailer.
I'm going to move the axle on the SledBed back about a foot. I fabricated a mount for a geared winch that fits over the tilt-latch, so I can tilt the trailer at water's edge and winch the boat up, then tilt it forward and lock it down. Very slick. One person can load a fairly large raft.