very nice! good job
if you're still searching for sealing, look at mcmaster's website! lol they have almost everything you'll ever need :P
I'm planning to do something similar this summer, i was going to go with aluminium, but after doing projects in carbon fiber, i'll probably go with that... only thing is that right now i think there is a shortage...
I'm still not decided whether i want it completely sealed or not... i fear it might trap too much humidity...