off the top of my head i know that hi-spec do that sort of brakect (be prepared for a long wait unless you pester them directly, and being in london you might even be able to pop in and buy them off the shelf)

as for the cossie caliipers, if you mean the 4pot ones then no as a bolt on job wihtou doing so drilling and tapping to get them to fit
the 4wd ones are a bolt on jobbie with perhaps a little machining to the brackets to get them to fit properly