Get a wooden box similar to this:
An iPAC2 control interface:
https://www.ultimarc.com/control-interfaces/i-pacs/i-pac2/
These buttons for flippers, and magnasaves:
Using these leaf switches and PAL nuts:
And a couple of these buttons for coin / start / select / etc:
https://www.ultimarc.com/arcade/buttons/classic-pushbuttons/
This will make a sturdy controller that will take more punishment than a tupperware or cardboard box.
Here you go: http://www.amazon.com/gp/product/B0054G6A8Q/ref=oh_aui_detailpage_o02_s01?ie=UTF8&psc=1
Remember though, the hinges are kinda crappy, and they don't come with latches.