What year is the Mercury?  I changed mine last year - it's a 1988 Mariner.  I had to remove the starboard bracket (but not the engine) and I replaced the motor and pump as an assembly which was about $400+ for the parts.  Check ebay - there are many later year trim components listed.  Mine was a bit unique and none were listed on Ebay at the time.  
Here is the thread I started almost a year ago.  There are some pics on the last page
http://wellcraftv20.com/community/showthread.php?t=7651
Good luck
Carl