I recall spending a night trawling through a parts catalogue looking for options and came up with nothing. Pretty sure the knurl diameter was the killer. 16mm or 16.8mm or something absolutely unique.
ARP apparently have some though I do not know part numbers sorry.
One my cars the aluminium space blocks are a winner, bolt the spacer to the hub, bolt the wheel to the spacer. They come with German TAC certification (at least they did a while back) and are perfect centre every time.
May be worth having a scroll back a few weeks, there was talk about the factory spacers, there may be a part number in there that can aid your search.