Kells 23 Strawler

[retrosub]

I'm resurrecting a Kells 23 Coaster (shoal keel sailboat akin to Cal 22 and the like) as a displacement powerboat with a cuddy. The balsa core decks and interior wood have rotted, so I'm gutting it and starting from the bare hull. When complete, it will look something like the PG25 Cabin (above the waterline).

I can't find good marine ply anywhere near me, so I'm going to order some. What thickness plywood should I use for the following?
Bow deck
Side decks
Cuddy sides
Cuddy top (arched)
Vee berth bulkhead
Cabin bulkhead (helm)
Rear bench bulkhead
Seat tops
Cockpit sole (egg crate structure beneath)

Of course I need a lot of glass and epoxy. Is there a shipping discount if I order all of it at the same time, or are there separate warehouses for these items?

[retrosub]

Here's a sketch of what I'm thinking.

http://gallery.bateau2.com/displayimage.php?pid=53289

Some photos of the hull in its current gutted state:
http://gallery.bateau2.com/displayimage.php?pid=53293
http://gallery.bateau2.com/displayimage.php?pid=53292