self timer

Last year I bought an OM4 on one of those online auction sites. I was pumped to start utilizing the in camera spot meter: an upgrade from my OM1.

It was a while before I used the self timer, and I seem to be missing the small screw that allows me to turn off the beeps as the timer counts down. Does anyone know where I might be able to find a replacement screw OR know of an alternative?

What screw?
To turn the beeps off, you have to move the self-timer handle towards the lens.
To set the self-timer, you need to move that same handle the other direction.
Mutually exclusive...