Hollow ball-top shafts for topfire button?

[Brad Lee]

Are these available anywhere, or does anyone have the means to make them?
I got to thinking this weekend that if so, it'd be "easy" to convert a regular balltop joystick to a top-fire. If I had a hollow shaft, I could dremel out an area at the top center of the ball to accomodate a button, run a length of dowel through the shaft, and when pushed it would make contact with a switch below the whole assembly(similar to to old wico boss atari sticks)             note: i Know I left out about springs and e-clips, this is just a brief thinking-though

1. I haven't seen these anywhere
2. I lack the tools to drill a hole through the length of the shaft
3. I could use threaded pipe but then I have no way to put a ball on top

Anyone got any ideas, or is this not worth pursuing?