I think I need a new muffler but is it called something else on a Subaru?

It may be a muffler but it can be several other items as well. You'll need to have someone put this car on a hoist and see where the exhaust leak is occurring. The condition of the remaining exhaust system will need to be taken into account as well when making repairs to the exhaust. Or just chrome everything and call it a Harley Forester! :)

Go under the car and inspect where your leak is because it may not be the muffler. Try running the car and looking and listening for the leak.