George, read the below e-mail from a guy that I found that builds them:
"I Built the hard deck myself. I've built five of them now and they work flawlessly. I put a ton of time into the design and build out. They run between $800 and $1000, depending on the options. I'll have one for sale at the end of this week, I'm laying the fiberglass and epoxy on two decks now. These boats act totally different with a hard deck. Much better riding characteristics across the board. Hit me up if your interested. email@example.com
Here's a couple links to him on youtube using his FC-470 with one of the hard decks he's built. Make sure and let him know that I recommended you!
YouTube - ‪FC470 Santa Barbara CL‬‏
YouTube - ‪GOPR0032‬‏