They also have a shorter one too. Check their website or, the pegs next to this button. I've wondered about it but, the longer one that someone replaced my Original's button with still works, so I've not make the jump to try the shorter one. It costs a little more, but it's the right size.
My desire is to find one that doesn't require so much pressure to engage. My son has a hard time pushing this one and the switch on my other original is MUCH easier to push.
Short starter button