Guys,appreciate any help on this.Looking to replace a porthole on my 20'boat in cuddy cabin.The porthole is a black plastic style.Beckson is the name of the manufactuer.It's a 5" x 12" style.I have found one site that has them although not exactly the same but they are pricy.Wondering if anyone would know where I could find a used one if possibble.Thanks for any help.