If you are going to the trouble of replacing, most here will highly reccomend upgrading to one with aluminum end tanks. It is a bit of a pain to replace and the stock plastic tank ones are failure prone. Sorry to clutter up your wtb thread, but I am just trying to help.
That being said If you want a stock one, don't pay very much for one. There are alot of them on shelves. I have one Id sell very cheap but I am unable to box and ship it for a while.