I recently aquired a tiki 21 that needs the crossbeams replaced . I wanted fiberglass beams but dismissed that idea after gathering data , I determined they were to flimsy ( sideways deflection under load ). I found alum beams at 800-704-2157 . I didn't write down the company name , but they quoted me 400.00 for three 3" i beams . I still need to make sure they can stand the load , but its the best lead i have found so far . Has anyone else found better answers . Quite honestly , I have looked more closely at building new crossbeams out of hardwood instead . Honduran mahognogany finished bright is my preference , with awlclear finish after varnish to keep the maintaince down . I am currently fairing with awlgrip fairing compound and i highly recommend all of thier products , i wouldn't use anything else on any boat . I have also designed an expandinding trailer for easy ramp launch . I' ll let you know how that works out and any thoughts anyone else has would be greatly appreciated .