This is a base for Sparkfun's line of Big Dome Pushbuttons (https://www.sparkfun.com/products/9181).
I printed this with ABS and the pushbutton snaps right into the top of the ring.
There are a couple different configurations you can print. Either a basic base for the pushbutton. Or, there's a ring with two built-in brackets for basic 8 ohm speakers and a base with a hole for a slide switch.
The bottom is attached to the ring by 2 M3 screws: https://www.mcmaster.com/#catalog/124/3077/=1c12237
The slide switch attaches with hot glue from the inside. The entire switch (including attachable wings) should be no bigger than 20mm x 8mm and the actuator length should be 4mm or shorter. I used a switch I had on hand and not sure where I purchased it from.
Audio Button Project
For my project, I connected the big pushbutton to the Adafruit Audio FX board via a Push-button Power Switch breakout, a couple of round 8 ohm speakers I had lying around and 3 AAA batteries. Then suddenly I had a self-contained speaker box that plays an audio file when the button is pressed.
The only thing I would do different is add a small arduino, like an Adafruit trinket, to send a kill signal to the Push-button Power Switch breakout after the audio has finished playing.