I'm pretty sure they will fit. I had the drag bars on my streetfighter and they fit on my Monster 1200s.
That is exactly what I did and it has completely transformed the bike! I actually am starting to like it a little bit better.Cool another SF to monster convert. I had a lady run into me from a stop sign and though loved the SF decided to get something new with the 1200s. Only complaint so far is slightly cramped over SF, hoping the bars, adjustable pegs and the touring seat I got solve that.
Looking into rapidbike down the line as well. What have you got on yours and how do you like it?