Belive it or not there is a guy in Delta Junction that seems like a reasonable option. He sells High-tech trailers which are aluminum and stainless trailers that are no more than galvinized trailers.
Here is a recent ad of his off of Craigslist:
I'm the Alaska dealer fo Hi-Tech Marine Boat Trailers. I have in stock four Hi-Tech Trailer Aluminum I Beam Boat Trailers, 25' to 29' , one 10,200lbs tandem, one 10,500lbs tri-axles and two 12,000lbs tandem trailers. I also have a 29'-32' 12,000lbs tandem trailer in stock.All trailers are made with Aluminum I beam,heavy duty aluminum cross braces, buddy bearings and stainless steel hardware. Galvanized torsion axles, wheels and winch stand. Trailers have fully adjustable cypress bunks and marine carpet. Kodiak dics brakes,LED Lights and more. Can order trailers from 19' to 42' and 7,000lbs to 18,000lbs See them at www.kjenterprisesllc.com
then call me for a quote. Call Dennis at 907-378-9489 9:00am to 9:00pm for a quote
If no answer please leave message or e-mail dennisgene@Hotmail.com