if you own a Benelli MR1 and would be interested in an aftermarket extended picatinny top rail (to replace the current rail and the open sights) you might want to check out the thread in the Black Rifle forum where this is being discussed. ATRS should be producing these in the near future.
http://www.canadiangunnutz.com/forum/showthread.php?t=693933
http://www.canadiangunnutz.com/forum/showthread.php?t=693933