You don't necessarily have to go through ebay. Your local muffler shop should be able to sell you some kind of a muffler and have it installed. This would probably be more cost effecient for you as you're getting the product and service from the same place.

Though you are looking for just a muffler, you really don't have any choice but to get the new muffler welded on. Though there are a couple of axle-back exhausts that are available for your car, you don't seemed to be interested in spending more than a hundred bucks.