I've never done it; however, in concept it should be doable using a bit of scripting.
Are you running the reports off a server or off a local machine? If ran locally, you could create a python script that is always running, listening to events that occur at the time that "submit" is pressed on the paramter form.
If an even is caught, the python program sends an LPR command to the printer of your choice, which could be parameter based, meaning you can pass the python script the name of the printer.