Hardtop, not 't-top', right? I thought t-tops were on center console boats.
Anyway, my guess is a cover to fit over the hardtop is a custom job. However, I don't see why the cover I bought for mine wouldn't work by just cutting from the bottom perimeter up to each post and sewing in zippers or velcro strips. Taylor-Made offers an 8oz acrylic/poly for about $275 that's semi-custom fit for a 20' walk around. I've been using one for a couple of years now and it's been fantastic. There are several fabric colors, go2marine.com or west marine are online sellers. The light gray stock number is 880610.
You can look up the trailerite semi-custom fit boat cover at
http://www.taylormadeproducts.com/catalog/ There's a nice navy colored one that would match the boat, but I wanted as light of color as possible for heat reflection. We get more sun here than rain or wind. It's held up in winter storms though, but we don't get freezing weather out here in cali.
I added a motor cover, but the swim step stays exposed. The cover goes over the transom, windshield, and bow, and railing. Will post pics if you wish (might take a few days). I don't trailer with it, at least not over 25mph, just down to the launch. It would flap way too much on the freeway. Great for storage though.
A sunbrella stock design will run $600 to $800, a custom probably well over a grand. I'll be happy if I get the 5years out of this one, that's the factory warranty. For $275, its and easy deal over 5 years.
My buddy kingj, with Vedette 208 here on the forum, has a custom sunbrella that covers his bimini and has sandbags around the perimeter since it's moored in a slip. Very nice cover, great material, but expensive. I think he was pretty close to a grand on it.
EDIT: BTW, I took the link from the taylor made site to boaters world and they ship them freight free for $180. What a steal-deal. Oh, the fabric is 6oz, not 8. They have all the specs for the fabric up there.
