I did a google search, masonite colorlok,got 42 hits.Several were class action suits and buyer beware reports.
I haven't used this product for many years,used to use it on garages,because it doesn't last.Once the outer surface is damaged it suckes up water like a sponge and falls apart.
I do believe it is still on the market,though it would probably be a special order item.
Wish I had better news,but I am just one poster maybe someone out there has more info.Luck