Unfortunately, my best advice is lost, along with the old board. But I'll try and salvage some of it.
Don't scratch-build. For realistic-looking ships (Elves, Brets, Empire), there are quite a few appropriate miniatures already out there.
I'll refer you to
http://en.wikipedia.org/wiki/Scale_model#Model_ships_and_naval_wargaming for a little history lesson on waterline ships.
IIRC, Man o' War was simiarly to 1/2400 scale. You won't get as much obvious size variety in your ships (real sihps didn't vary by quite as large a margin), but you can easily put together a very nice-looking fleet with a little bit of web work.