HI,

I've just had a Roland Micro Cube amplifier in for repair and it uses the same type of Alps switch you mention. ( It's also broken )

This is a simple single-pole latching push-button switch, so electrically, almost anything rated for an amp will be good enough.

Alps no longer make the same part, so you'll need to find something which looks the same and fits the original hole.

My repair is easier, because the replacement part doesn't have to match anything.

Graham.