Here is the reply I received from Grady White regarding the manufacturer of the cabin windows on the 2002 Marlin 300. I will contact them tomorrow and see if I can get any of the parts. I will post their response.
"The cabin windows on the 2002 300 Marlin was made by Taylor Made (PH# 941-782-3323) and their item # is 879-4821A SIGNATURE WINDOW. I do not believe parts are still available on these windows. We installed them during the build of the boat. Hope this is helpful".