From Dan Simpson's Item List, I've discovered that there is a Chain of Drakkas, tailor made for multiclassing fighter and arcane spellcaster classes together. I've never heard anyone else refer to it.

All I want to know for the time being is:

Has anyone found it? Yes or No, I don't want to know where exactly it is just yet.

Is it at a set location, such that when I play it in the future I know it will always be there?

I found and it's great. I think it's always found in the same place (if that was your question).

If by saying chain of drakkas you mean that armor with no spell failure(I don't remember it's name though) I've found it too and it's at the last dungeon in chapter 6 and I don't think it's a random drop either so you should be able to get it.