So quite a while back I ended up with a whole bunch of those RC car remote antena's. The ones that retract down into themselves. Well for some reason I decided I would cut the tip off the top and the threaded portion of the bottom. when I pushed it back into itself it all came out the bottom revealing various sized aluminum tubes. Now I find a use for just about every diameter that the antena has to offer, exhaust tips, axle shafts, drive lines, stacks for semi trucks.
what your looking for-
this one has both drive line and exhaust tips
exhaust tip (note this has the rolled edge on the tip because this was at the top portion of this section of the antenna)
A little slow here...but that's a great tip Crash. That gives me a reason to go into the RC area now. Of course...I have to find a hobby shop that's close to go to...ooorrr...I guess I could order a few off line...HHHMMMM