Andrew:

I vote for Option 2. It's always been a puzzle to me why the Finders for the Account and the Department basically show the same information. I would say that the user enters the base Account code correctly at least 95% of the time. If the user then selects the Finder on the Department field, they are looking to see which Department(s) match the base Account.

If the Department name can also be displayed as Doug suggests, that's a bonus.