rear adjustable strut tops

Have you looked into having some machined up?

Yeah, your best bet is to machine it up if you have the tools/skills for it.
 
The rear "adjustable" camber ones are very very rare, only a handful of company had them, and most of them are discontinued.  I have only seen "Toda", "Tein" and I believe some Apexi N1s.....
 
BUT, all of the "adjustable" ones I seen are 4 bolts and not 3.....
 
Anyhow, good luck ! ! !