No intention to drop out. Peel ply well from the dressmaker or from your supplyer of epoxy, glass carbon etc.
Plastic tubing? For the bagging of spars just ask the guy who sell the Peel ply to give you some extra of the "tubes"he uses for packing the stuff he is selling you.
The blue tubing seen in the pic you get from the store where they sell pneumatic stuff (about 50 cent/m)