Thing's you can do. Taking out the fuse box & towel dry. Call local junk yards for a used boxes. Searching on ebay & similar sites. Last the dealership.
dump rubbing alchol in the fuse box, alchol will evaporate the water out from the fuses. Also find where leak is coming from and seal the box with caulking.
The best thing to do is try to dry it out and if you can't you can go to the dealership and get a new fuse box and install it. It is easy for a do it yourself job.