Hey Billitt, I haven't heard of Mitchell Motor Parts, but I would just spend the cash for a new one and avoid trouble down the road. Not real warm and fuzzy with knowing there could be flakes of rust or something plugging up my fuel lines. Go with a major supplier, they have too much at stake to sell you junk. Paddock, Year One etc. If you aren't worried about stock, go with a nice fuel cell. That requires a nole in the trunk though. If you are going stock that isn't an option. I'm going with a 16 gal cell since my gas tank was junk.
Maybe someone else can give you some good vendors.