Triazolam. Hard to find. You're not going to find any that are easy to find that are shorter acting than Alprazolam. Honestly, how experienced are you with benzos? Have you tried Clonazepam (klonopin), while it is actually one of the longest acting benzos, have found it isn't very sedating and is more of a anxiolytic. This will eliminate that groggy feeling you do not like.
Another option is to insuffalate/rectally use the benzo, this will make the duration 50-75%.