There's a company called Gibco Flex Mold that manufactures the non-skid mold for a number of manufacturers, including
J/Boats. The mold is a flexible sheet that contains a non-skid pattern. You pour gelcoat onto the area and press the sheet into place. As the gelcoat cures, it takes the shape of the mold.
I called to inquire and they send me a free sample pack. Part of the pack was a business card-sized piece of mold that precisely matches the basket weave pattern of J/30 decks.
I do not know the price of the mold, but it's worth looking into.
There are also ways to make your own mold using a section of good deck as a pattern, though I've no experience with that method.
Here's the link:
http://www.gibcoflexmold.com/ [This message has been edited by Jason King (edited 04-29-2008).]