I wonder if the carrier from the Challenge Furai would fit onto the Silvio's seat?
http://www.challenge-recumbents.com/html/index.php?taal=en#furai
BTW I don't own a Silvio. I wish!
Yes and no.... Certainly the design is plausible, but the odds of that matching up to the Silvio seat are slim to none. You could no doubt adapt it, or if you knew somebody that could build you one... Certainly it could work.