Reconditioned Boat Trailer (New Brakes) | eBay
This is pricey and wont sell so I'd open a dialog and see if he'll take an offer of 2k which it is definitely worth. If this is a Degraff then it's the same model as my big trailer but I have pads instead of bunks.If you want a twin I think fillipflop on this forum might have a couple of 3.5 ton twins at his yard and he's a good guy to deal with.
Beamishken made a good case for a twin trailer but I love my triple axle cos the extra wheels really help keep the load steady But my 8.4 open Rib is a lot heavier than yours.
I have to be Honest and say that I would expect a 10m cabin rib to come in at more than the weight of yours but I guess I have been around heavy commercial Rib for too long.
I still think youd be better off with a Yankee Aloominum trailer.