I'm wondering does Disney sell 1/2 day park passes? The day we're arriving we'd likely only be in the park from 4 or 5 until closing......was wondering if they sell 1/2 day passes?
Not AFAIK. However, if your'e going to be there for a couple of days anyway, the cost of adding on one more day to a multi-day park hopper is pretty cheap. For example, for my summer, trip, the cost difference between a 3 day and 4 day park hopper is $15, I believe.
They do offer 4p.m. passes but only for those going to conventions as you have to purchase them through the organization hosting the conventions. WDW does this as well, I have purchased some for an upcoming convention in Sept. and they are really cheap! Ultimately, upgrading another day would be the cheapest route as suggested by PP's.