I would go with Graham’s idea or very happily pay the $300 fee for transport.  
With Graham’s idea you could almost have a little floating dock for the price of the transport if you are a diehard DIY guy.
I really prefer the idea of your trailer salvage barge being separate for safety.  I have done lots of dive salvage for these type things gone bad! Lol.  
Now if you consider how much time you will need to re-pack your hubs, cost of barrels, straps and line, stress of the towing ordeal then the calamity of the stuck trailer in the water when you cant get it out $300 sounds like a bargain.   Maybe consider buying a cheap tow vehicle and trailer to leave on the island.

Bob (palatka)

>> On Feb 22, 2020, at 3:06 PM, Graham Stewart <gstewart8 at cogeco.ca> wrote:
> ?In Kingston Ontario  I was able to buy used 55 gal plastic drums from a local fruit vendor/food distributor for $20 each. They would be easy to strap to the trailer frame, have enormous buoyancy and can then be used afterwards to make floating docks or swim raft. If you need the drums anyway, using them to transport the trailer would be essentially free.  Four would probably do the job. 
> 
> I have attached a picture of my floating boathouse, located on lake Ontario, that I built using the drums. They are incredibly strong. I have left mine in the lake all through the winter freeze up for the last 15 years and they are still as good as new. When I used steel drums they rusted out in a couple of years.
> 
> Graham
> 
> Graham Stewart
> Agile 1976 Rhodes 22
> Kingston Ontario
> 
> 
> 
> 
> -----Original Message-----
> From: Rhodes22-list [mailto:rhodes22-list-bounces at rhodes22.org] On Behalf Of KillarneyLake
> Sent: Thursday, February 20, 2020 10:31 PM
> To: rhodes22-list at rhodes22.org
> Subject: Re: [Rhodes22-list] Trailer Sailer Sails Trailer
> 
> Your plastic drum idea gave me an adjacent idea—those metal caged water
> buffaloes! They are inexpensive when purchased used, they seal, they can be
> securely lashed and are quite buoyant.
> 
> 
> 
> --
> Sent from: http://rhodes-22.1065344.n5.nabble.com/
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