Mrs. Rain Dog,
I feel your pain. Last year, we had a similar problem and I looked all over the place for a replacement that would even come close to fitting, precisely because I didn't want to spend the $$ on new Bomars.
I removed our forward Bomar and bought a new Lewmar
(I think it was the Lewmar
Ocean 19 1/8 x 19 1/8) from Defender. I knew I needed to do some woodwork for the inside gap (the frame doesn't extend down far enough to meet the headliner), but when I placed the new hatch
in the cutout, the flange around the base of the Lewmar
did not cover any of the existing screw holes on deck. I would have either had to do some fiberglass work or add some sort of aluminum or wood base (like a washer for a bolt). I'm not good enough with fiberglass to make it look good, and I was concerned with doubling my chance of deck leaks (deck to base seam and base to hatch
seam). In the end, I sent the Lewmar
back, had the Bomar stripped and anodized (much cheaper than paint
and more durable on aluminum, I'm told), and then fixed my cracked support flange with some JB Weld. The anodizing color matched almost perfectly and I have had no issues with the JB Weld fix.
If I had to do it again and couldn't refinish my existing hatch
, I would bite the bullet and get the new Bomar. While the Lewmar would work, it requires semi-extensive boat modification and is not as heavy duty as the Bomar. The Bowmar is much more substantial and can be made water tight, whereas the Lewmar frame is much thinner and flexes easily.
Hope that helps,