don't want to crap on your thread; but I know that you can
get this exact muffler for around $210 from most local performance shops (at least in my area). And if I'm not mistaken, there was 2 more of these posted within the last month for considerably less than this one. They were slightly used; but you can see where I'm going with this.
If you really want to get rid of this; I suggest biting the bullet & lowering the price a bit. You're gonna lose a bit of money; but normally you will when trying to re-sell aftermarket stuff.
Just my .02