One source (there may be others) for original Aquasport gelcoat colors is Mini-Craft of Florida, Inc. The company has a list of available Aquasport gelcoat colors going back to 1990.
According to a Mini-Craft customer service rep, gelcoat colors supplied by Mini-Craft are based on the original mix codes supplied by the specific boat manufacturer. The rep cautioned that the exact original color may not be an identical match on a hull that is even a few years old due to exposure to a range of natural elements including ultra-violet radiation - that 'whites' tend to yellow while darker colors tend to fade.
For hulls older than 1990, there are a couple of options. At the top of the page on the link below, you can send a Hull ID Number to Mini-Craft to check gelcoat availability. A better option for older hulls is to send a sample chip to the company for a custom mix.
https://www.minicraft.com/retail/aquasport.htmTheir customer service people have been as great to work with the two times I've used them in the past. Color matches were excellent, too.
