Hi David,
There isn't any logic able to be configured for the Events to do that in Performance Management given current functionality. I think its a great idea but would need to be submitted as an Enhancement Request via an Idea post here in the Community site.
Closest might get at first glance would be something like this. I took a guess at Metric Family hoping it gives you some ideas for what to configure. Can also set the Condition Type to a Standard Deviation for one of the disk space used metrics to catch other sizes.
Another alternative would be setting up a Group with only disks with the specified sizes as members. Apply individual event rules to each group via the Threshold Profile to Group association to delineate which ones get the given event raised.
I believe most disk items are synced to PC per my lab system. In case your disk items fall under some type not synced to PC you'll find you can't set up a group with them as specific members. To resolve that you'd need to enable the sync of those types of items.
How to synchronize unsynchronized Component elemen - CA Knowledge
Hope that helps even though it's not a straight yes.
Thanks,
Mike