Forgive the delay but Barnes (DuPont) has been out of the city and I finally reached him today.
He was very friendly and says that he will have their "model shop" make up a half-dozen tubes or so to your specifications.
I told him you would drop him a note with a drawing giving dimensions, etc. They will probably machine these but he says that
the molded ones will be mechanically superior--some kind of skin affect.
So the ball is back in your hands.
He tells me that these are number of molding shops around who could produce these in quantity. Also Nylon is already being
used for cases for syringes and the like.
He would like to hear how your tests, [ . . . ] repeated autoclavings, etc., affect the tubes.