Hi NB,
My trailer was part of a system that was being trialled in a contract competition for the UK Ministry of Defence. It was built in 2003 by the MESA Corporation of Switzerland to a very high specification, after failure to win the contract quite a number of these trailers and similar types were disposed of.
When I saw it, my immediate thoughts were 'Yes that will do me very nicely!'. So an immediate purchase at $4200 plus shipping, of course I had just considered that it was a bargain and not thought the project through to where it is now. First off was that although the axles were rated at 5.5tonnes each, the suspension was only rated at 2.25tonnes per axle and neither the tires nor rims were rated for the speed and load that I was looking for. Further that in order to meet type approval for road use I needed a math calculation from an approved company that the trailer could be safely rated at 23500lbs GVW and maximum speed 60mph, together with appropriate modifications to meet all our UK road regulations. The bed is 15 feet 5 inches clear length.
Anyway the result of this was that I needed to have the suspension resprung, wheels and tires changed out, ABS braking system implimented. The cost of work was $1000 for the supporting paperwork and $8600 for the work and materials. Making a total of $13.8K, still cheap, for a very nice trailer that will carry up to 19000lbs load; it has a nice manual hydraulic tailgate too and I now have 4 brand new tires and wheels to dispose of. The final alterations have been to turn the pintle over from the top of the drawbar to the bottom and remove a 60mm packing piece to give me a level bed when towing behind the Mog and as the bed was only half covered it is now full covered in with 6mm steel checker plate. I have to say I am very pleased with the result in terms of performance and cost for what to all intents is a brand new trailer, I have been told that a similar trailer new would have cost me probably around $53K.
Finally you asked about availability. The answer is yes there are a few still available and it would probably be worth shipping from the UK to the USA. If you have further questions or need assistance give me a shout.