Having tried it once, welding a bow sprit on the hard
is harder than it looks and the splatter may do damage to your gel coat.
Rather why not try to come up with a fabricated shape that would do the trick.
Two SS plates that would fit tight against the outside of the existing fitting welded together at the bottom and a roller at the end. Drive out the existing roller fitting and use a longer pin to hold the extension. You may want to drill and put a bolt further back on either side.
Use some cardboard to mock it up.