2005 Mini Cooper S water in Battery Box
 

My mini seems to have been leaking water into the battery box for awhile now so it seems. I can not find where it was coming in but I am looking into the rear door handle area I have seen that there is a seal that goes bad there. When I pulled the battery out, aftermarket bought the car used, I also pulled out the battery fuse box. I saw that the 200 ampere fuse has a little corrosion on it same as you would find on your battery terminal so I cleaned it up and looks like I should replace it. I can't find the fuse only just the whole box which I don't need. Also I found that the previous owner must have cut the jack off of the cable that routes to the fuse box. The connector is there and the next cable that goes from there to the positive terminal connection is connected to the fuse box. When I disassembled the fuse box I inspected the connector for the squib wire and the wires that route near the back hatch and it looks like the pins are no longer there due to corrosion. Where can i find replacements beside going to a pull a part place? Thanks for any help and sorry for the long post.