[frnkeore]

I like the buttons and make my own.

Here are some of my spares. I keep them on a 1/4" dowel and use both 3/8 and 1/2" sizes. The black one is store bought.

If the 3/8 hole is not a press fit or, I need more advance/retard than the 3/8 bushing will yield, I ream the timing gear or sprocket, to .499 and drill and ream a new .500 dia bushing to position. In this way I can get any degree movement I want and not just +- 2*.