Welcome to the board M.Hunter
I am sorry I can't give you specific information about barriers, but if you search the archives of the adhesions message board you will find information previoussly posted by members of the board.
All I can tell you is that there are a number of barriers in use in various countries around the world, with some available in one country and others available in another country. As for the success rate I have read mixed comments about the success and failure of these devices and I know that personally I am not prepared to have a surgery to place a barrier at this stage as my adhesions are extensive & I am not really keen on facing another surgery.
I believe that all barriers are expensive, I know the few times I have asked my doctors about them here in Australia prior to surgery they have always commented that they are expensive and that the success rate for them was very mixed at this time.
I hope that gives you a starting point, please feel free to ask for help anytime. We offer friendship, support & understanding here.
Love & gentle hugs