That sounds like bad luck. Did you have any security device fitted to the trailer when it disappeared?
I would guess that Ribeye just buy in trailers from a manufacturer, so you might as well look around to get whatever is the best rather than their choice.
I have an SBS trailer which seems very well built, but they are based up in Wolverhampton. There are a couple of more local trailer builders - Parrymore Trailers in Staines http://www.trailers.gb.com/
and RM Trailers in New Alresford http://www.rmtrailers.co.uk/
Also, Jono Garton (on this forum) is an Admiral trailer dealer.