I replaced mine with a boneyard unit.
I was mainly annoyed with the copper wedge that someone had jammed in one
of the fuse sockets. In retrospect, that fuseblock was mostly OK and the problem was the loose spade lugs that comprise the relay sockets.
How badly hosed is your fuse block?

If you had a fire then the problem was one of those dippy spade lugs was
loose that was carrying heavy current...it became a resistor and disipated
heat causing that mess.

You need to fix the spade lugs as well as the melted fuseblock.

You can rework the tired old lugs, tighten them, and solder the crimps.
Sadly nobody seems to know where to get new replacement lugs.


Bill