I acquired my two Prideaux loaders from a site in the UK which strongly implies they are originals (... but carefully avoids actually claiming that! ...) Expensive - although by no menas as high priced as confirmed originals - and I talked them down a fair bit by purchasing two. Still paid too much, really, but also decided I'd never get a chance at a genuine one, so I spent some spare money ....
I've used them in the Era of Expansion match at one or two Musters ...