Rebuilding Heater A/C control?

The plastic vacuum switch portion can be replaced. I dont know what else about it might fall apart.

All the buttons for the control fell out, I got them all back in but when you push any of them in they just push the vacuum piece off the back. Those 4 pieces in the picture to the right of the control also fell out when I was unbolting it and I have no idea where they came from.
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