i have seen a few adapters going about on e bay before, but taking them 5x 130, you might fight it hard to find ones to 5x100, i imagine that because the holes were at the same diameter as the bolts holding on the adapter, but i dunno, i am sure if its possible your cheapest and easiest option would to get a engineering firm to whip so up for you on a lathe, using probably steel, i dunno if aluminium would be too soft or not???