I'm going to guess that they're Bomar hatches. It might say it on them somewhere, like the latches or frame. You can try here:
Also try Great Lakes Skipper http://greatlakesskipper.com/categor...and-parts.html
somtimes the OEM stuff is tricky to find on the site, but they do have a wide variety of parts. Depending on the year, you might be able to get replacements right from a dealer. If there's not a Bayliner/Searay dealer in your area, call the closest one, they will all ship directly to you.