Terminal Server Printers

I am creating a locked down RDS profile for vendors to use when they log in in to our network. I am trying to figure out how to hide all printers except the vendor's redirected printer. When the print from our application, all I want them to see is their own redirected printer. I don't want them to be able to accidentally print to another printer in our office. I've looked everywhere in the GPO options for printers and terminal services and I don't see anything for this. Any help would be appreciated. Thanks!