I doubt you will find a better quality switch. This is the only image of the circuit board I could fine. The power switch is at the top right of the image. You should be able to find a generic 6 pin PCB mounted switch to fit.

If it's in the On position you could make an inline switch for the power supply using something like this switch. Just cut the power supply cord at the amp end and wire the switch in. Obviously leave enough cable at the plug end to work with. Better yet, get a male and female connector and don't cut the power cord at all.