oh man i want one... that "need for tweed" setting with the riviera.... awesome...
oh, and the "fender" reverb was actually produced by a company called accutronics... they originally used them for hammond organs, but fender used them in guitar amps, and we all know what happened then... but anyway, if you want a brand new reverb unit, you can get one directly from accutronics... they have an ebay store, and you can find out what kind of reverb unit you already have on their website (if it's not listed, send 'em an email, they will be able to tell you)
That way you don't need to have an old fender reverb for your new epiphone amp...