Hi Will,
Rather than trying to make something fit which can cause more problems than it solves, try and find the correct jewel, it might take a while but the watch aint going anywhere 
i think diamond powder is the only thing that will cut the jewel, that has to be imbedded into something the right size to cut the hole bigger. It can be done but not to easy to get a good result. You could turn down the pivot but then they were made that size for a reason. If you can find a way to get me some dimensions i might be able to find one for you
Paul.
