That looks like it will work fine. The 9 volt out will be nice for your amplifiers. As long as the unit is of decent quality you should like it.
Almost sounds though like you would be better off just getting an inexpensive Radio with external input until you get your computer fully up and running. The radio will allow you to do much more and you wouldn't even need to mess with the HD radio. You should be able to get a decent radio for not much more than one of those line drivers.